That One Boss / Fire Emblem Heroes

"I'm surprised you made it this far. But now...I will stop you here!"

—Legendary Ryoma, and what the other intro quotes might as well be on Infernal and Abyssal Difficulty

Fire Emblem Heroes has its share of frustrating bosses, whether it be from the Grand Hero Battles or Tempest Trials, even for experienced players.

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Grand and Bound Hero Battles

• Regular Idunn in her Bound Hero Battle alongside Fae. The map is littered with dragons, and is mostly open with just some trees to block off a mage cav waiting at the north. The Blue Fafnir is equipped with Iote's Shield (to remove the flier weakness) and Dull Ranged (to further impair ranged units), and has Light Breath+ to buff any nearby allies. Said Fafnir also has Guidance, so if you're not careful, that Guidance will be used to warp Idunn right over to you, ready to ravage your units. She's a complete menace to fight, especially on Infernal, since her Bonfire is fully charged. Her stats are enormous, especially considering her Demonic Breath basically prevents her from being debuffed, canceling any debuff and gaining +5 Atk/Spd/Def/Res instead. She'll also get this if her HP is less than full. With a massive 72 HP, 52 Def, and 44 Res, unable to be affected by visible debuffs, and can potentially get even higher, she'll stand tall as a wall for your units to overcome. She mercifully has no Distant Counter, so she can be chipped away at, but then the other units can be a problem. Pack a dragon slayer and proceed with caution.
• Fallen Female Corrin in her Bound Hero Battle alongside Fallen Male Robin. Already considered as a Demonic Spider, with her default Savage Breath, Dragon Fang, Atk/Spd Solo, and Sudden Panic, she also comes with Rouse Atk/Def, but what she gets in this Bound Hero Battle makes her reach SNK Boss levels, as alongside Fallen Male Robin with the inflated stats, she gets maximum special cooldown reduction, where on Hard and Lunatic difficulties she has her Dragon Fang be at 1 cooldown, where it's normally 4 cooldown, but Infernal takes it down to 0, meaning that she will always have her Dragon Fang ready especially with consecutive attacks from her, and Melancholy+/Witchy Wand+ will not stop her in her tracks as she fires off 38 damage Dragon Fangs like it was nothing if everything is in her favor in Infernal. She also starts near a healer with Physic+, so chipping her HP away won't work until you take out the healer first. Fallen Male Robin, despite his natural Distant Counter in his Expiration along with his Ignis being at 2 cooldown at Hard and Lunatic difficulties and 1 cooldown at Infernal, is a lot more manageable to handle, since he is slower, has a relatively tame skill kit, and more importantly, has more counters thanks to being Green, a Dragon, and Armored, unlike Fallen Female Corrin who is Colorless, a Dragon, and Infantry. In their Bound Hero Battle reruns, thankfully, their maximum special cooldown is at the correct numbers while their initial special cooldowns are at those numbers, meaning that skills like Pulse Smoke and Melancholy+/Witchy Wand+ will now work on them, meaning that the maximum special cooldown reduction in the battle's initial release seems to be actually an oversight by the developers when they set their initial special cooldown, but Fallen Female Corrin is still a major threat despite this change, whereas Fallen Male Robin is now a minor threat in comparison to her thanks to this change.

Legendary, Mythic and Emblem Hero Battles

• Fell Vessel (Legendary Robin possessed by Grima) was our introduction to Legendary Hero Battles, and she doesn't disappoint. While Fell Vessel isn't quite as scary as her male predecessor, she makes up for it by having the typical difficulty-based buffs, such as inflated stats and a fully-charged special at the start of the stage. Because of her nature as a colorless unit and having Cancel Affinity as a passive, there are no units that resist her attacking type, so she will tear a huge chunk of HP out of whoever she gets to hit - and even if they can take the Bonfire special, they still need to avoid a follow-up from her high base 38 Speed to survive. Either the tank needs to be extremely bulky, have a lot of Speed and Resistance, or someone needs to outright nuke the Fell Vessel Robin before she can hit back (easier said than done without a Falchion, because she gets a passive Def/Res buff from Dragonskin when defending). This is to say nothing of her allies that flank her, who are running a wide array of Breaker, Fighter and buff skills to punish anyone who thinks they can just walk up to Robin and win.
  • During the first revival of the map, players were treated to the new Abyssal difficulty. In this mode, Fell Vessel Robin now has a ridiculous 46 Speed and 81 HP, making most of the previous One-Hit Kill strats moot. Another nuance to Abyssal is enemies using Sacred Seal skills; in this case, Grima packs Atk Smoke along with her Res Smoke to drop both stats on your units caught in a wide area if she lands a hit, making her a lot harder to kill on the backswing (and a lot easier to kill your units in return). She's not the only one, either; many of her allies have been given skills to hit obscene speeds, and some of them are outfitted with skills that decrease your units' speed, making it very easy to get rushed down if you don't pick your positions and targets carefully.
  • Oh and this battle is pulled to be part of the first lineup of Limited Hero Battles as well in April 2020. You're forced to deploy heroes from Path of Radiance and Radiant Dawn, and what's worse is that you're only allowed one Dancer, and out of all of the Tellius heroes at the time, there are only two healers from there, one being seasonal and the other being 5* locked, and only one unit has a weapon that is effective against Dragons, and that unit is also seasonal. If you weren't lucky enough to pull or make a team out of any of the Game-Breaker units from there, you're in for a bad time. Fortunately, the Abyssal difficulty is based on the Infernal stats, so it's not as bad as later Limited maps that do use Abyssal stats.
• Legendary Tiki is another doozy of a Legendary Hero Battle. You're mostly confined to the bottom-left of the map (barring some insane movement tech), forced to let all of the enemies come to you, and there are a lot of enemies. Most of them are ranged as well, which means your units will take a lot of cheap shots from behind the walls unless they are also ranged (or have Distant Counter). Especially notable is that there are two very deadly mounted mages; one of them a Green Cavalier with a Gronnraven tome to hit both Blue and Colorless units (like any healers you brought), and an even meaner Red Cavalier with a Rauðrblade tome to turn all of his stat buffs into attack power with which to obliterate. This is without getting into Tiki herself, who is an armored Blue Manakete and has all the bloated defensive stats that implies, cheekily sitting on the lone defense tile in the center of the map to discourage you from leaving your corner. Making matters worse is her With Everyone! skill that applies Def/Res+5 to herself and anyone beside her at the start of her turn (like the Red Cavalier with the bladetome!), making the flood of enemies even harder to weather. She is also a monster in combat, having Fierce Breath and Bold Fighter for cooldown reduction on either phase and the Speed to double anyone that isn't stacking Speed themselves, so she will fire off her Special every combat unless you outright stop her from attacking. On Abyssal, on top of her ridiculously inflated stats, she even comes with the Hardy Bearing seal, completely shutting down strategies revolving around skills like Desperation.
  • Stepping back a little, remember what we just said in Legendary Robin's entry about early LHB maps on Abyssal difficulty not using Abyssal stats? Tiki's is not one of those early maps. Infernal and Abyssal difficulties had their proper stat applications this time, which makes this map so much tighter of a challenge when limited to units from one game. In this case the game in question is Sacred Stones, which has a very sparse selection of support units: while their only refresher (Tethys) is fairly accessible, their only healer (Winter Eirika) is decidedly less so on account of being 5* locked and seasonal, and her Armor class can be both a blessing and a curse. Even though you can get a free Sacred Memories Eirika from the Heroes' Path, you will need hyper-invested units for this challenge, and at least one of which needs skills dedicated to overcoming Tiki's crazy skillset and bulk - not even Brave Ephraim or Duo Ephraim can take her on without backup.
• Legendary Eirika is downright unfair on higher difficulties. The first dick move the map pulls on you is the group of enemies that suddenly spawn in the hallway south of your rather restricted starting point: a Blue Cavalier with a Bladetome sandwiched between two other cavaliers each with Hone and Fortify who will obliterate all but the sturdiest Green tanks if not killed immediately. The second dick move is that when Eirika joins the fray herself, it will usually be alongside a legion of Green enemies to prevent you from tanking her with a Blue, which is a problem when her pre-charged, makeshift Black Luna likely oneshots any other unit type. The third and final dick move is the Axe Cavalier that is loaded on durability and has Lunge, existing for one purpose: to survive a round with his target and swap places with them, often dropping them right in front of Eirika. Most winning strategies for this map involve walling the Greens until your ranged units can snipe Eirika from over the wall, but she even comes with Deflect Magic on Abyssal to ensure that mages like Reinhardt can't one-round her.
• Hríd's Legendary Hero Battle demonstrates how powerful he's designed to be, as his weapon grants him a follow up attack and denies his foe a follow up if his foe has a debuff of any kind. Almost every enemy in this map has either a Ploy, Threaten or Smoke skill to debuff your units with (Hríd even comes with Panic Ploy on Abyssal, taking full advantage of the HP inflation). Basically no matter where the player is on the map, they're getting hit with some debuff, which Hríd will prey upon. Making matters worse is that Hríd starts moving on the second turn before the reinforcements have even finished spawning, and he's a Cavalry unit. If you haven't created a gap in the debuffs and done it quickly, Hríd will rush in and end your run in the blink of an eye.
  • It's worth noting that Pheonixmaster1, a youtuber well known for his Free-to-Play guides, considers Hríd's Battle the hardest one to beat with just Free-to-Play units.^note The second hardest one, Legendary Eliwood, took him 12 hours to beat, as until Brave Ike's refine there was no such thing as a "Free-to-Play super-tank" to engage the Panic-based Breather Level strategy.
  • Hríd eventually returned for a Limited Hero Battle, this one limited to Shadow Dragon / Mystery of the Emblem characters. This is a problem for two reasons: firstly, many of the Archanea units are from the early days of Heroes with poor stats compared to today's bruisers, which makes it hard to compete with Hríd and his legion of monsters without serious investment. Secondly, many of the Archanea units who are equipped to fight Hríd are seasonal and thus very hard to acquire, which includes Harmonized Tiki and the young characters from "The Start of it All". Without seasonals, this limits the map's strong choices to a small handful: Young Minerva, Phina, and the two Krises. Young Minerva is mercifully free, but the other three are all 5*-locked, and Phina herself is also the only Archanea refresher. If you're summon luck is lacking, good luck clearing Abyssal or even Infernal with only Young Minerva and three deadweights.
• Legendary Azura's Legendary Hero Battle wasn't That One Boss or That One Level the first time around, but it definitely qualified when it came back as a Limited Hero Battle.
  • Azura can give extra turns, and whatever she feeds that extra turn to gets 3 Mov if they're Infantry or Flying (as she will almost never refresh an armor knight). This creates a de-facto Interface Screw as the Danger Zone is no longer reliable, especially due to her tendency to catapult the Firesweep Sword Flier across the map on the very first turn. Since she tends to hang behind her flunkies, she rarely, if ever, is in the line of fire.
  • The main threat is the player being swarmed by enemies. Because of Azura being able to catapult enemies across the map making it so that nowhere is ever safe, defensive play is the natural response... except that will get you swarmed. On turn 2, two Wary Fighter armors spawn while the player is bum-rushed by a Flash Staff Cleric who will turn your units into sitting ducks as well as the cavaliers with Wo Gun and Slaying Spear (eff armors). Turn 3 spawns a Brave Bow Flier on the top left corner, who, if refreshed by Azura, can easily reach your units and kill them with her nuclear offense and Cancel Affinity (to shut down TA raventomes). If you don't one-round the enemies you will get swarmed, while if you do you are left in striking range of a very large variety of units Azura can send your way.
  • The game of choice this go around is Shadows of Valentia, and the Valentian cast might as well be split into three groups, all of which have problems with this map:
    • Units with Gen 1 bases who do not stand a chance against Abyssal-level enemy stats.
    • Units who cannot take a hit and must stay very far back lest Azura throw a unit across the room.
    • 5* exclusives, including several extremely strong seasonals, which comprise of much of the Valentian cast that can actually do something about the map, including most of their Game Breakers leaving the unlucky or poorly equipped player with very little to work with. Valentia's 3-4* pool and welfare units are riddled with problems that require extensive investment to make them serviceable for this map.
• Eliwood later repeated Azura's stunt: easily-cheesed Legendary Hero Battle on inception, but nightmarish when Limited. Eliwood's gimmick is to apply Atk/Def+6 and Bonus Doubler to whichever of his teammates has the highest Atk — except many of them are tied, so the buff hits all of them. Chill Atk won't fix this either as it will simply land on Eliwood himself. We're not exaggerating when we say you need someone who can counter Bonus Doubler, otherwise this map is nigh-impossible. The game of choice for this Limited Hero Battle is Awakening, and while it does have units that handily counter Bonus Doubler, they are all 5*, and majority of them are Legendary Heroes themselves: the best are Legendary Robin, Legendary Chrom, and the Fallen Morgans. Chrom is a pure crapshoot due to only appearing on Legendary Hero Banners, and Robin and the Morgans were very easy to pass over in banners that featured "sparking".^note Robin appears on Legendary Hero Remixes, but before her own Remix she was generally inferior to other choices. The Morgans were great units from the get-go, but had the misfortune of sharing with Fallen Edelgard. Free unit Aversa with her Sudden Panic weapon is helpful for the lower difficulties, but will fall off in Infernal and Abyssal where enemy HP is too high. Lacking any of the above, you'll have to build a unit from scratch to deal with Bonus Doubler, which in itself can be a bigger investment than you bargained for if you don't already have one. The one bright side is that there's no shortage of dancers or healers unlike in other Limited battles — Olivia is free, and while none of the Awakening healers start with a Panic staff if you want to go that route, it's easy to inherit.
• Legendary Roy. While it looks like the large amount of enemies Roy spawns with can be easily bottlenecked by abusing the Sword Cavalier with the Firesweep Sword, this is easier said than done as he's flanked by two ranged units of the other color, so the only practical way to do it is with a strong ranged colorless tank (the Blue unit has a Blárblade tome and thus needs to die before Roy buffs him). Adding to the complications is that the Lance Cavalier starting in the Southwest has Drag Back, which not only pulls the tank out of the bottleneck but puts them in range of a Sword Flier with a Brave Sword and Miracle. The enemies are set up in a way that they try to push you into the Southeast corner, which is where the "gotcha" happens when you're pinned between Roy, an Axe Fighter with a refined Poleaxe to destroy your cavalry, a Red Manakete with Quick Riposte, and a very speedy Blue Flier with a Blárraven tome.
  • With Legendary Roy's Limited Hero Battle variant in March 2021, it is more difficult to handle without premium heroes and/or skills. The heroes you need to complete this Limited Hero Battle are from Genealogy of the Holy War and Thracia 776. While Regular Reinhardt is a good enough unit and there are easily available dancers, you're going to need much more than that to beat this map, as the variety of units coming your way will overwhelm your units with ease while also shaking off Reinhardt's attacks, with the only reasonable units to field that can take out most of the other enemies and keep up with the pressure, especially on Abyssal difficulty, are 5* exclusive units, which includes Regular Sigurd and the Legendary variants of Seliph and Leif.
• Yune. As you might expect from a Physical God, Yune's Mythic Hero Battle is one of the hardest to date, and a good demonstration of how minor changes to a unit's best stat can make or break you. Her Sabotage Res and Chaos Named skills will often ensure that your units will be debuffed unless they have enough Res to avoid it (must not be 3 less than Yune's), which is easier said than done on higher difficulties with Abyssal capping it off at a staggering 52 at base - which also means any magic unit that isn't Red need not apply. Her weapon is also similar to Hríd's in that she gets a guaranteed follow-up if the target is debuffed (and Atk+6 in-combat for good measure), and with a pre-charged Glacies coming off of that massive Res stat, that kills you. Abyssal caps her skillset off with the Deflect Missile seal too, just in case you thought a Bow unit would be a quick win. Not helping is the Sword Fighter with Panic Ploy (on the map right away) and Thief with The Cleaner (spawns in the bottom-right on Turn 2) in case you try to counter her debuffs with your own buffs. The crux of the difficulty comes from most of the enemies having enough Speed to double your units naturally, and attempting to counter this with your own fast units will end up with their Speed being debuffed by Chaos Named unless you can safely navigate Yune's blind spots.
• Naga picks up where Yune left off. Starting with the obvious, Naga has Dragon Effectiveness and her Divine Fang skill also gives Dragon Effectiveness to any allies who start their turn beside her (a common occurrence with the narrow map layout), a good number of which are ranged, mounted or both. Naturally this makes bringing dragons to Naga's map an incredibly bad idea unless they can manage to tank only the non-Divine Fang enemies. In the event you don't bring any dragons with you, Naga still has a few nasty tricks: firstly she takes a page from Legendary Alm's book and can stack her own Spd to ridiculous levels, capable of reaching a terrifying 79 Atk and 67 Spd on Abyssal between her weapon effect (+3 to all stats for every Dragon or Dragon-Effective ally near her), Atk/Spd Bond and Odd Atk/Spd Waves from allies. Said allies are also problematic on their own, as one of them is a Troubadour with Wrathful Gravity to restrict your movement and a huge Res stat, and the other is a Bow Fighter that is also stacking Spd along with Swordbreaker (and brings the Darting Blow seal on Abyssal for good measure). Without good movement tech and/or units powerful enough to deal with the HP inflation, it's all too easy to get boxed in by the offensive rush Naga subjects you to.
  • And then the Limited Hero Battle hit. The featured game this time is Binding Blade, which is a terrible unit set for Naga. Most Binding Blade units are ill-equipped to handle a map full of speedsters, and many of the "noteworthy" options are dragons, which of course are liable to get ripped in half by Naga's Divine Fang. Worsening matters is that the refresher options are limited to exactly one unit: Larum, who is a rarity even among 5-Star units due to have so few summoning focuses. With the exceptions Legendary Roy, Legendary Lilina or Harmonic Catria, the only serviceable options for Naga's map are passion projects made out of Binding Blade's many junk units.
• After a long dearth of difficult maps, we got Altina. A Sword Flier with a crazy skillset, Altina has a dual-phase Brave weapon, Distant Counter, negates her flier weaknesses, and has Vantage to make things interesting if you can't kill her in one round - and you probably won't, because she can get a disgusting 50 Def / 53 Res on Abyssal on her own merits on top of the HP inflation (and can get an extra +4 from the Green Fáfnir she starts beside). You'll almost certainly need a designated Altina-killer with an Area of Effect Special + Hardy Bearing, Windsweep or a Firesweep weapon to take her down on Abyssal, unless you're packing an Astra nuke with Atk in the high 80's to oneshot her. Despite all of this, Altina is actually less threatening than her allies, as all of them have some means of dramatically altering your units' stats such as Panic Ploy, Smokes and Lulls, and a couple of them have Lunge to screw up your formation. The worst examples are the Fáfnirs: they're fast, they're bulky, and two of them come with Chill Atk and Chill Spd respectively (which is very bad when the other enemies on the map are beefy and speedy as is). The actual challenge of the map is keeping the Altina-killer out of danger before Altina and her Fáfnirs sandwich you, which can be quite a chore since the Fáfnirs start spawning at the same time Altina starts moving.
• Mila is our first example that takes advantage of the newly-increased stat caps for Infernal and Abyssal. The majority of the difficulty comes from the allies she brings with her that all get +2 to all stats during combat from her Nurturing Breath - which may not sound like much, but it gives them a frustrating amount of bite and bulk that can be just enough to end your run. Mila additionally has Rally Def/Res+, and one of the standout enemies is the Bow Flier with a Firesweep Bow and both Close Guard and Distant Guard, dealing free damage while boosting her allies - all of these things combined can easily make a troublesome enemy refuse to die when you most need them to. Another source of headaches are the powerful tankbusters: a Green Mage loaded on Atk/Spd and using Lull Spd/Res to make sure they work, and a Red Thief on Turn 2 sporting The Cleaner and Panic Smoke so your buffs will be used against you. Mila herself isn't as threatening as her compadres, but she's still nothing to sneeze at. She'll never hit you more than once, but her defenses are massive: 55/49 base on Abyssal, enhanced with the Aegis Special, Bracing Stance 3, the Distant Defense seal, and the reinforcement Sword Knight gives her Def/Res Gap; ranged units could have to punch through a cozy 72/66 spread on top of Aegis. You must bring a dedicated tankbuster or anti-dragon Hero, or Mila just won't die. Worse yet is that she inflicts Isolation on any of your units within a cardinal direction of her position with Mila's Turnwheel; it activates when Mila's visible Defense is higher than her prey's, and since Abyssal boosts her Defense to unreachable levels, it will activate. This causes things to turn ugly fast if you rely on Assist skills for safety, and since she has Rally Def/Res+, she has the annoying habit of moving around to Rally her goons even before she aggroes, constantly changing the Turnwheel's affected area to keep things interesting.
• Freyja and Triandra were already That One Boss in the story missions (see their entries below for more info), but one thing they didn't do there was tag-team you... until now. The first Dual Boss Mythic Hero Battle, both Freyja and Triandra are now armed with their playable skillsets to send the player into a whole new nightmare. Triandra still has Flower of Sorrow and Frightful Dream to wreak havoc on your units with Def/Res and Guard debuffs from across the map, but now she also has Atk/Spd Push 4 and Spd/Res Rein to be a genuine threat if she decides to attack. Abyssal gives her 66 Atk and 50 Spd base along with Iote's Shield and an accelerated Miracle charge. And making things even worse is her master Freyja, who naturally is the most threatening thing on the map by a country mile: Abyssal Freyja has 64 Atk and 59 Spd base, which is augmented by Nightmare Horn, a fully-charged Luna, Atk/Spd Solo 4, Pulse Smoke, Fierce Stance, and her new B skill Binding Necklace. What this does is if she's not beside an ally during combat, she gains +2 to all stats, inflicts -2 to the enemy, and steals the enemy's visible buffs and debuffs them for the same amount for that round of combat. Unless you have the Red nuke to end all Red nukes, neither Triandra nor Freyja are likely to go down in one round and will slam into you like a freight train in response, to say nothing of Freyja catching you with Binding Necklace active. The mooks on the map are minor annoyances compared to the Mythics, but many of them only need to do one thing: ensure Freyja's Spd advantage through the myriad of buffing and debuffing skills they have on-hand (even the Axe Knight has Atk/Spd Link!). Other than that, the only standout mook is the Cleric armed with a Flash+ staff to inflict the Anti-Counter status effect, and Bonus Doubler and Lull Atk/Res make her surprisingly sturdy.
• If you're ill prepared against Legendary Sigurd, he will rein in and bring pain. He bring a dangerous skill kit that will exploit his Mighty Glacier statline to the fullest, with Atk/Def Catch 4^note user gains +7 Atk/Def during combat if either the foe is either at full HP at the start of combat or has a [Penalty] inflicted on them, and gain an additional +2 Atk/Def during combat if both conditions are met, Crusader's Ward^note reduce damage taken from consecutive attacks by 80% if the foe attacks from 2 spaces away, and Fatal Smoke^note negate skills that heals the foe during and after combat, and inflict the [Deep Wounds] status effect to the target and all foes within 2 spaces of that target after combat, which prevents the unit affected by it unable to recover HP, all which he has equipped already starting from Hard difficulty, but alongside that is both a weapon and special that makes him a pain: Hallowed Tyrfing and Holy-Knight Aura. Hallowed Tyrfing gives him -1 maximum special cooldown, and if his foe is at 75% HP or above at the start of combat, he gains +5 Atk/Spd/Def/Res, a guaranteed follow-up attack, and reduced damage taken from his foe's first attack by 40% if either he initiates combat or his foe wields a ranged weapon. That alone is difficult to handle, but it gets worse with Holy-Knight Aura, where it is a 2 cooldown special (which is brought down to 1 thanks to his weapon) that gives him +1 movement at the start of his turn, boost his damage equal to 25% of his Atk during combat when it activates, and when it activates, after combat he gives himself and all allies +6 Atk and +1 movement, even if he was KOed during that combat, meaning that not only he moves 4 spaces, but his allies will avenge him with higher movement and stronger Atk if he dies and Holy-Knight Aura activates, meaning that the one who KOed during the enemy phase will suddenly have a lot more units choking down onto them. Alongside with his 69 Atk, 32 Spd, 49 Def, and 35 Res on Abyssal difficulty, he is going to be difficult to take down alone.
• Ashera brings a map that's as difficult as it is weirdly basic. The arena is very much an arena, a diamond-shaped board with no obstacles whatsoever, featuring only four defense tiles that Ashera starts on. The difficulty comes from the map's attempt to recreate the final battle of Radiant Dawn, wherein Ashera had a Battle Aura that warded off attacks. A Lance Knight and Axe Knight play the part of the aura — by using Near Save and Far Save respectively to intercept attacks directed at Ashera (or their nearby friends, including each other), and the Axe Knight also has a seldom-seen high-tier skill in Distant Ward to counterattack mages with his Far Save. Also unique is that they aggro along with the boss instead of moving immediately and also have Swap to keep Ashera safe from long-range attackers, meaning you must deal with them before getting at Ashera. Baiting Ashera away from the Knights is also made difficult for three reasons: the first is that Ashera hits like a goddamn freight train, taking a leaf from Yune's book with a precharged Glacies that will obliterate the target if it goes off. The second is that Ashera's unique C Skill, Order's Restraint, buffs her allies (and if she starts the turn near three of them, herself as well) for Atk/Res+6 and Null Panic so you can't neuter her damage easily. The third is the Troubadour that starts behind her, armed with a Flash staff to disable your counterattacks and Far Trace to retreat to safety afterward (if she has spaces left to move, but she often finishes on a defense tile). The combination of Ashera and these three enemies pretty much makes the Mythic Hero Battle by itself; the rest of the enemies are underwhelming, mostly running interference or employing Lunge/Drag Back to drop an ally in Ashera's range.
• Legendary Female Byleth. Compared to Legendary Male Byleth whose only gimmicks were a shareable Null Follow-Up within two spaces and a stronger Ruptured Sky, Female Byleth's kit is quite a bit meaner: she has a shareable Tempo^note all forms of Special acceleration/negation from the enemy are disabled within two spaces of allies, gains [Null-Follow Up] and +7 Atk/Spd just for being near those allies, and can warp beside those allies essentially giving her the range of a Cavalry without being hindered by most terrain. With Atk/Spd Ideal 4, Lull Spd/Res, and an extra +5 to all stats from her weapon, she will double you if she gets to attack, and with a pre-charged special it will hurt. The enemies that accompany Byleth don't seem threatening at first, but Null Special can make them surprisingly hard to deal with, especially in higher difficulties where Special acceleration/negation are almost required to offset the enemy's stat bloat. And this is of course without factoring in that Byleth can use her many allies as warp points and just end any unsuspecting units that aren't Green tanks. The map becomes much simpler if Byleth is taken out early, but this is easier said than done since the map is cut off by a cliffside that will quickly be bottlenecked by enemies, and your team starts on the cramped side. Hope you sparked for Ascended Fjorm!
• Medeus, despite his map being only filled with magical units, is this, especially on higher difficulties. He bring Def/Res Ideal 4, Canto Control 3, and Glacies, and Deflect Magic 3 on Abyssal to be a big pain, but his Shadow Breath and Assured Rebirth are the dark evil cherries on top, where Shadow Breath gives him +3 Atk, targets the lower defensive stat of foes if they wield a ranged weapon, inflicts -6 Atk/Res on the foe during combat and prevent the foe from performing a follow-up attack if the foe either initiates combat or is at 75% HP or above at the start of combat, and at the start of his turn grant +6 Atk/Res and [En Garde] to himself and all allies within 2 spaces of him, where [En Garde] prevents non-AOE special damage taken outside of combat, and Assured Rebirth grants him a guaranteed follow-up attack if he has more Res than the foe during combat, and reduces damage taken from attacks and non-Røkkr AOE specials by 4% for each point of Res he has over the foe, up to 40%, and 20% for each Dragon or Staff ally within 2 spaces of him, totaling up to 60% damage reduced, so you're not chipping his HP away with skills like Pain+ and AOE specials, and even then there are 4 Staff allies on the map that can heal him up just to be a pain. Alongside his Mighty Glacier statline at 64 HP, 48 Atk, 20 Spd, 41 Def and 47 Res on Infernal and 80 HP, 56 Atk, 26 Spd, 49 Def and 55 Res on Abyssal, with his entire skill kit active, he effectively has 79 Atk, 56 Def and 68 Res on Infernal, and 87 Atk, 64 Def and 76 Res on Abyssal, on top of having Glacies at 49 power on Infernal and 56 power on Abyssal, you might as well give up targeting his Res with magical units and try to take him down with physical ones, but the amount of physical heroes that are not ranged and have high Atk and Res are few and far between, with Legendary Marth (appropriately) pretty much being one of the best hard counters against him and his dragon minions with his Remix skillkit despite his low Res.
  • And there's his Limited Hero Battle version in April 2023, where you're forced to use The Binding Blade characters, which means that you need someone with high Res and can tank against Medeus and his goons while also be strong enough to take him down, but with the large amount of magic units on the map and status-inflicting Clerics, not even Legendary Roy with his Remix skillkit can tank them and take them down without significant assistance from other allies or boosts to his Res, and those without premium units like Ascended Idunn or Bridal Harmonized Catria & Thea are out of luck.
• As you'd expect from Askr's patron deity, Askr himself is a tough customer. He's a Colorless Infantry Beast with stat weights like Medeus above, has the loophole-abusing Def-based damage reduction that infamously turned Spring Maria into a meme, comes with a fancy new Bulwark skill line that blocks enemy movement and heals him after combat, and his C Skill and grants [Resonance: Blades], [Resonance: Shields] and Time's Pulse to himself and all nearby allies if one of those allies is from a different game... wait, what? Aren't the generic enemies from Askr's own game and thus wouldn't trigger it? Unfortunately, Askr thought of that — he brought Legendary Marth with him, Askr secretly being a Dual Boss. Even worse is that Legendary Marth comes with his Remix kit which not only inflates his stats to ludicrous levels if he's near an ally, but prevents counterattacks and follow-ups if you're more than 4 Spd slower or are a dragon (and if he's near an ally, you will be slower). The Abyssal versions of both bosses would be bad enough alone, but the slew of buffs Askr gives out turns even the cannon fodder into persistent threats, to say nothing about Askr and Legendary Marth together being a force of nature if you don't separate them.
  • And then comes his Limited Hero Battle version in June 2023, where you're forced to use Shadows of Valentia characters, and alongside the other enemy units rushing you down, you need more than just premium units like the Legendary variants of Alm and Celica, Bridal Harmonized Catria & Thea and Halloween Duo Duma & Mila to get through both of their sheer defenses and stats and their mooks without the enemy overwhelm one of your units as well, even on Infernal difficulty.
• While Arval in their Mythic Hero Battle can be handled with the right units due to a large variety of choice from many Fire Emblem games, their Limited Hero Battle version in July 2023 is another matter entirely. You are forced to deploy (New) Mystery of the Emblem characters, and Arval themselves have 64 HP, 48 Atk, 30 Spd, 26 Def and 47 Res on Infernal, and 80 HP, 56 Atk, 36 Spd, 32 Def and 55 Res on Abyssal, and thanks to Arval's Duality granting +9 Atk/Res and weapons triangle advantage over the primary colors, all but colorless units (with the exception of Nagi) will have trouble dealing meaningful damage against them, even with their lower Def, Duality and Rite of Souls together create an Omnibreaker effect, so units have to nullify it through their skills or status effects, their Rite of Souls inflicting [Guard] on foes within 3 rows or 3 columns centered on them at the start of their turn if they have more Res than their foe, meaning that your units are going to have a difficult time triggering their specials, and they are just one charge away from activating their Glacies on Infernal and Abyssal, and the latter two are helped with Arval's Atk/Res Tempo 3 to make sure that Glacies triggers on retaliation and prevents foes bypassing [Guard] through +1 special buildup effects like Flashing Blade, and anyone from (New) Mystery of the Emblem that fits the above criteria while also able to handle other enemies as well are too few and far between, even among premium units like Medeus and Gotoh, not to mention that at the time of this Limited Hero Battle, there is only 1 Dancer from (New) Mystery of the Emblem, and is a rare one to summon to boot, so players are going to have a difficult time getting those 20 Divine Codes on Abyssal or even Infernal difficulties.
• Gotoh & Fomortiis are two incredibly bulky Colorless Mythics who must be fought on the same Mythic Hero Battle map. Gotoh's Brilliant Starlight inflicts -6 Atk/Res on his foe, neutralizes his foe’s bonuses to Atk/Res, neutralizes effects that prevent his counterattacks, restores 7 HP to him after combat, and grants himself and all of his allies within two spaces +6 Def/Res and a status buff that reduces damage from AOE specials by 80%. His unique A skill, Gift of Magic, inflicts a whopping -10 Atk/Res on his foe, gives him a guaranteed follow-up, and reduces damage from consecutive attacks by 80% if he initiates combat or if his foe is 2-ranged, and he also has Joint Distant Guard and Guard 4, which has a much more lenient HP threshold at 25% or above to activate in addition to inflicting -4 Atk and reducing damage from his foe’s first attack by 30%. Trying to defeat Gotoh with just 2-ranged units is nigh-impossible thanks to his A skill, and even 1-ranged units will need to be able to hit hard to get through his astoundingly high mixed bulk. Meanwhile, Fomortiis's Ravager inflicts -6 Atk/Def and -1 special cooldown on his foe, grants him +1 special cooldown per attack if he’s transformed, and reduces damage from his foe’s follow-up attacks by 80%. His unique A skill, Nightmare, inflicts -10 Atk/Def to his foe and reduces damage from their first attack by 30% if they initiate combat or are at 75% HP or above, and if his foe initiates combat without defeating him, the nearest units within 4 spaces of the unit who attacked him will have their actions ended immediately. The action ending effect from his A skill can quickly disrupt strategies when trying to chip him down, especially multiple dancer and hit and run strategies. In addition to that, he has A/D Far Save 3 and will immediately transform after turn 1 and remain transformed for the rest of the battle thanks to his B skill, Beast Follow-Up 3, removing the conditions needed to transform in addition to giving him guaranteed follow-ups, which means that if you want to freely attack him with a 2-ranged unit without having to resort to counterattack disruption skills, you’ll need to do so on turn 1. Oh, and both Mythics have their specials fully precharged to make trying to survive their attacks a very tough endeavor. On Abyssal, Gotoh has the Null-Follow Up 3 seal and Fomortiis has the Mystic Boost 3 seal, which, along with their massively inflated stats, makes them even more dangerous to approach and defeat. Having to fight one of them would already have been incredibly tough, but being forced to fight both of them pushes their map to being one of the hardest ones to complete.
  • And then comes the absolute hell that is the Limited Hero Battle version in September 2023. Thought that was bad enough? Now do them with only Engage characters. This is particularly bad not just because they use their actual stats on all difficulties, but the pool of Engage characters is very limited, with only 14 characters to choose from, and out of all of them, 4 of them are FTP-friendly, with the addition of Regular Male Alear being gifted a few months back, and 4 out of 5 of them are Red, which means they fold against Blue units on higher difficulties, and that there were at the time no healers and dancers available to them. This version of the battle requires premium units like Legendary Female Alear, Alfred, Céline and Citrinne to even have a chance on Lunatic and higher just to get those Divine Codes, and this was just released a day before Legendary Female Alear's Legendary Hero Battle debut banner ends, meaning that one of the best units for this map is not going to be available to summon for the entire duration of this Limited Hero Battle.
• Legendary Female Alear in her Legendary Hero Battle is a Lightning Bruiser Infantry Green Dragon that will punch you down thanks to her skillkit. Her Dragon's First giving her -1 maximum special cooldown, the standard Dragon effect of adaptive damage against ranged foes, allows her to attack twice in one round, and grants her +5 Atk/Spd/Def/Res during combat, inflicts -4 Atk/Spd/Def/Res on the foe during combat and additional -3 Atk/Spd/Def/Res for each of her allies that are from a distinct Fire Emblem title from each other within 3 spaces of her, totaling up to -10 Atk/Spd/Def/Res during combat (but for this battle it's a max of -7 thanks to not having another ally from another title spawn with her like Askr's Mythic Hero Battle map) and reduces damage taken from the first attacks, including both attacks from the first round from attack twice effects, and non-Røkkr AOE specials by 40%, all which activates if she is at 25% HP or above at the start of combat. Despite lacking a support partner to activate her Dragon Blast's Damage Reduction-piercing and Damage Reduction effects, it will still boost her damage by 50% of her Spd during combat when it activates. What's more is that she has Atk/Spd Finish 4 and Atk/Spd Pledge to give her more Atk and Spd while also having Atk/Spd Finish 4 grant true damage and recovery, Null C-Disrupt 4 granting 30% damage reduction, inflicts debuffs on the foe's Atk and Spd and makes her immune to effects that prevents her counterattacks and Atk/Spd Pledge granting the [Pledge]^note +1 special buildup per attack during combat status effect to consistently activate her Dragon Blast. All of that combined and you got one very fast dragon that has basically with everything in her favor 84 Atk/Spd, 53 Def and 57 Res on Infernal, and 92 Atk/Spd, 61 Def and 65 Res on Abyssal. What's even worse is that the Sword Fighter she starts with has Rally Def/Res+, Spd/Res Ruse 3 and Inf. Null Follow 3 to buff her up even further and potentially debuffs your units as well. Finally, to add salt into the wound, while you could at least poke her at range in Infernal and below, the same cannot be said when she has Dist. Counter (D) as her Sacred Seal in Abyssal, which synergizes well with her Null C-Disrupt 4, meaning that you have to find a way to one-shot her and bypass her Damage Reduction before she counterattacks with double or even quad punches, and trying to find someone that can even tank 2 or 4 attacks from her are few and far between, especially if she's triggering her Dragon Blast and getting an extra 41 damage on Infernal and 46 damage on Abyssal.
  • Thought that was bad enough? The Limited Hero Battle version in January 2024, like the above Gotoh & Formortiis Limited Hero Battle version, forces you to deploy characters from Engage, which has a limited pool of 19 characters from that battle, and, while there are a few FTP Red characters that can take on Legendary Female Alear, the fact that said limited pool included 1 dancer (who is limited himself) but still no healers yet since that battle means that she along with her cronies will still bring trouble and pressure your units, with premium units like Veyle, Diamant, Alcryst, Winter Yunaka and your own Legendary Female Alear being basically required to collect the 20 Divine Codes on Abyssal, Infernal or even Lunatic.
• Emblem Marth & Mythic Lumera on their Hero Battle map are an infantry sword and a blue infantry dragon respectively with Lightning Bruiser stats and the skills to make them truly formidable. Emblem Marth goes all in for combat, starting with his Hero-King Sword, which gives -1 Special cooldown, deals effective damage against dragons, and if his HP is at or above 25%, he gains a bonus to all stats equal to 20% of his Spd + 5, reduces damage from his foe’s first attacks by 40%, halves his foe’s percentage based Damage Reduction skills, and gains the Desperation effect. He also has the skills Atk/Spd Finish 4, Inf. Null Follow 4, and Potent 4. Potent 4 inflicts - 4 Spd/Def on his foe during combat, reduces damage from attacks during combat and from area-of-effect Specials by 30%, and if his Spd is equal to or greater than his foe’s Spd - 20, he triggers Potent Follow X%, which is an additional attack immediately after his standard follow-up attack. Unlike other units with this skill, Emblem Marth can make his extra attack at full power thanks to his pre-charged Special, Lodestar Rush, which deals damage equal to 40% of his Spd, gives him the Null Guard effect, reduces damage from his foe’s first attack by 40% if his or his foe’s Special is ready or triggered during combat, and if his Special is ready or triggered during combat, then Potent Follow X% is set to 100%. This means that he’ll be attacking three times in a row against most units and likely kill them, as they simply won’t have the Spd to avoid his Potent Follow. Mythic Lumera opts for a more supportive role with her skills while being fearsome in combat in her own right. Her Monarch’s Stone gives her -1 Special cooldown, adaptive damage against 2-range foes, and if her HP is at or above 25%, she gains a bonus to all stats equal to 25% of her foe’s Atk - 4 (for a minimum of +5 and a maximum of +14), deals damage equal to 20% of her Spd, reduces damage from her foe’s first attacks by 40%, and gains the Guard effect. She also has a pre-charged Miracle at 2 cooldown, Rally Def/Res+, Atk/Spd Scowl 4 to deny pre-charged Specials from triggering, Atk/Spd Ruse 4, and Dragon’s Monarch. This skill lets her apply Divine Vein (Stone) to spaces within 5 rows and 5 columns around her after she acts. On top of that, if there is an ally within those aforementioned spaces around her, she gains +4 to all stats, Null Guard, reduces damage from her foe’s attacks by 30%, and her allies within those spaces also gain the former two effects during their combat. On Abyssal, Emblem Marth has Deflect Magic 3 and Mythic Lumera has Dis. Counter (D), making 2-range units no longer safe against her unless they can prevent her counterattacks. The sheer difficulty of taking out both of these units makes this map just as brutal as Gotoh & Fomortiis, and even that map had the small mercy of having both of them start far away from each other, which cannot be said for Emblem Marth & Mythic Lumera. Since they’re adjacent at the start of the map, you’re all but forced to engage in combat against them while they reap all the benefits from being near each other.
• Emblem Ike is an extremely tough boss to take down thanks to his synergistic kit and Mighty Glacier statline. His Emblem Ragnell gives him -1 max special cooldown, Distant Counter, and boost his Atk and reduces the foe's Atk equal to 25% of the foe's Atk at the start of combat, -2, with a minimum of 6 and max of 16, and allows him to ignore any field stat debuffs he has, skills that prevent his counterattack and inflicts -X special buildup per attack on him, all which activates if he is at 25% HP or above at the start of combat, Great Aether is a 4 cooldown special that allows him to deal damage equal to 40% of his Atk when it triggers, increasing by 10% for each attack the foe does to him, forces his foes to attack first and have any of their follow-up attacks go before he can attack, reduces damage taken from attacks equal to 40% and from consecutive attacks by 70%, both inflicted by -10% for each point of special charge he needs to get it ready, and when he triggers his special he inflicts 5 damage and +1 special cooldown to all foes within 3 rows or 3 columns centered on him and he recovers 10 HP and an additional 5 HP for each foe he inflicts it with this, up to 50% of his max HP, and Laguz Friend 4 inflicts -5 Atk on the foe during combat, halves his non-Special percentage-based Damage Reduction, gives him -2 special cooldown before his foe's first attack and reduces damage taken equal to 20% of the greater of his Def or Res during combat if he has an attack or defensive special that has 3 or more max special cooldown, boosts his attack equal to 20% of the greater of his Def or Res during combat and ignores the foe's non-Special percentage-based Damage Reduction if he triggers an attack special that has 3 or more max special cooldown, and his next attack is boosted equal to 20% of the greater of his Def or Res during combat and ignores the foe's non-Special percentage-based Damage Reduction if he has a defensive special. Combined with his Def/Res Finish 4 to further boost his defenses and damage and recover HP when he triggers Great Aether if he is within 3 spaces of an ally, Canto Control 3 to prevent his foes from performing Hit-and-Run Tactics with Canto near him, and Quick Riposte 3 as his Sacred Seal on Abyssal to have his follow-up attack be able to finish the foe off if they somehow survive his Great Aether when his foe initiates combat and he is healthy enough and you got someone that is a major pain who will pressure you once he starts advancing. It requires specific strategies to take him down without much hustle like bypassing his absurd Damage Reduction or preventing him from triggering Great Aether, but this gets less viable on higher difficulties, with Infernal giving him 66/52/19/49/46 and Abyssal giving him 82/61/25/57/54, meaning that with all of that combined he will shrug off a lot of damage and would most likely either one-shot one of your units or deal a lot of damage and restore a lot of HP, potentially undoing all the little damage you dealt to him in the process.

Tempest Trials

• Veronica, the final boss of the "Dark Clouds Over Awakening" Tempest Trials. As the first boss to introduce the Tempest Trials game mode, at the time, she was no pushover, with high stats, Renewal, and Quickened Pulse to accelerate her Bonfire, so she was always recovering HP and being one step closer to nuking one of your units at the start of her turn, even when you used your second team onward, and was escorted by heroes with ridiculously inflated stats, including the likes of Game Breakers Hector and Reinhardt. What's worse, this is before many of the quality of life changes that came ever since, such as stat boosts for bonus units and 20% HP removal for remaining enemies when your team lost for the remaining backup teams. It's telling that ever since that Tempest Trials, all of the future Tempest Trials bosses do not equip a Sacred Seal, let alone a dangerous one at that.
• Brave Ike, the final boss of the "Less than Heroic" Tempest Trials. After the relatively easy Julia boss fight from the preceding Tempest Trials, Ike serves as quite the wake-up call. Steady Breath complements his already high physical bulk, and his Aether special activates much faster than usual thanks to the combination of said skill and Urvan. Urvan also grants him reduced damage from consecutive attacks, meaning you can't easily kill him with a Brave Sword or by attacking from a distance. You can't just cheese him with Horse or Flier Emblem either, thanks to his Beorc's Blessing skill, which nullifies bonuses on Calvary and Flying units. To top it all off, he has just enough speed to not be doubled by most unbuffed mages, and he's definitely not going down in a single hit. In other words, bring a very fast Rauðrblade mage and a way to buff the Speed stat or die.
• Fell Reincarnation Robin, or Fallen Male Robin, the final boss of the "Invisible Ties" Tempest Trials. Due to the way final boss maps of Tempest Trials are laid out, the player often has to either deal with range overlap if they try to bait out enemy units, or wait for the enemies to start approaching, especially in maps where units don't start adjacent to each other and thus are missing their crucial buffs. The player's then presented with a choice: bait out Grima immediately but also contend with at least one or two other units at the same time, or wait for Grima to approach to initiate against him. Do so at a risk however, as Grima is a terrifying enemy phase monster. This is thanks to a combination of his absurdly high attack—which is bolstered further with Fierce Stance—the ability to fire off his incredibly powerful Ignis very quickly thanks to Vengeful Fighter, and the ability to hit the lower defensive stat of a ranged unit with his weapon, which happens to have Distant Counter built in. The player needs to bring either a Falchion user, a powerful red mage with Desperation active, or an Armorsmasher+ wielder, lest they face Grima's wrath.
• Picnic Flora, the final boss of the "Taste of Spring" Tempest Trials. She's a red dagger armoured unit with great Atk, gigantic Res, and a weapon that capitalizes on said Res. Her unique weapon reduces her attacker's Atk and Def equal to half the difference in Res, capping at -8 to each stat. This essentially boosts her survival, lets her deal more damage, and helps patch up her kind of alright Def. She's also got Mirror Stance to boost her Atk and Res even further should you try to engage her, but if you try to let her engage you, you're in for a nasty Bold Fighter, which lets her not care about her low Spd and potentially even activate Iceberg against her opponent. She's also got Armour March and is next to an armoured unit, letting her approach you much more easily. She's surprisingly difficult to take down, and making matters worse is that her map is full of forest terrain, which she also doesn't care about if she's got Armour March active, while you have to be wary for your more grounded units. Thankfully she lacks Close Counter, the skill that would have made her quite possibly the most frustrating Tempest Trial boss in a while, so as long as you carefully bait around her, any anti-armor unit can get in and hurt her, but you still need to be careful if she does get close on her turn.
• Summer Helbindi, the final boss of the "A Promise of Joy" Tempest Trials. What he lacks in Spd, he make up for it in incredible strength and bulk. He has high HP, which couples with Panic Ploy to make any unit cardinal to him have their buffs inverted, a high Atk which lets him put dents in even blue units, and sky-high defenses, with them reaching 45 Def and 42 Res on the highest difficulty. His native weapon, the Sandford Spade+, also increases his Attack and Defense by 4 in combat if he has any visible buffs, while his Atk/Def Link lets him get even bulkier and hit even harder if anyone uses a movement assist on him. He also has Rally Atk/Def+, which means that not only will he be buffing one of his allies by +6 on Atk/Def, he also will be doing it often enough that he will more likely be the last foe on the map. And to top it off, he packs Ignis as his special - couple that with his attack, colossal defense, and myriad of ways to further increase said stats, him triggering that will almost certainly result in a One-Hit Kill for one of your units. Fortunately, despite his strength, he's incredibly easy to double.
• Fallen Halloween Female Robin, the boss of the "Ever Two Halves" Tempest Trials+, is a nightmare to deal with if you're not prepared, as she is pretty much a stronger and more mobile Fallen Male Robin. Unless if you have a dedicated Dragon Killer or using Halloween Ena, you're not going to enjoy this one. She is a lot stronger than her original Legendary counterpart before she got her refine and updated skill kit, as with her Dragonscale giving her an immunity to Bows and other anti-flier weapons and if the foe happens to be at 100% HP or initiates combat, she can even inflict -6 Atk/Res of them, making them more susceptible to her attacks, as well as charge up her special faster when her foes attack. She might not have any offensive specials, but she's packed with Noontime and her Moonless Breath makes her heal her HP as well if she's near allies, making it so she won't be dying anytime soon. Worst of all is the map layout - which unless if you're bringing in fliers, there's really awkward terrain that's VERY hard to tell apart.
• Harmonized Spring Myrrh & Nah, the boss of the "Familiar Stranger" Tempest Trials+, takes Power Creep even further than many past examples of Tempest Trial bosses. Thought Fallen Halloween Female Robin was bad? Myrrh & Nah are even worse. They're a Colorless Dragon Flier, giving them a large amount of range to move and thus wipe your team out on top of being a Mighty Glacier, with their Atk, Def and Res all being incredibly high. That alone is bad, but they also have their Lilac-Jade Breath, which, on top of making it easier to activate Noontime (as in, one attack to charge it up), grants them +5 Atk/Spd/Def/Res and reduces damage from all attacks and AOE specials by 40% if the foe either initiates combat or is at full HP at the start of combat; Dragon's Ire 3 to ensure they can always counterattack with a guaranteed follow-up attack if they're at 50% HP or above at the start of combat; and Atk/Res Rein 3, meaning they hit even harder and weaken their foes further. This makes them one of the single hardest to kill units in the game, because realistically you won't be able to one-round them since you can't even attempt to fight them without them almost completely killing you in one round, especially if you initiate against them. The fact they don't have their normal A skill, Distant Counter, should be a clue of how overpowered they are; they don't even need it to win. Their only weakness is their Dragon and Flying traits, on top of low Spd, but their damage reduction most of the time makes that a moot point unless you either capitalize on that with skills like Spurn, bring someone with dragon effectiveness, or a strong enough bow unit with Deadeye, they're going to easily wipe out your team. The fact that they always start off with a Cavalier ally next to them, which can include characters with buffing utility or someone like Duessel, makes it possible to fight them when they already have extra buffs going into battle.
• For characters original to Heroes, we got Nifl in the "Ice & Flame 1" Tempest Trials+. The patron deity of the land of the same name, Nifl is an incredibly fast and hard-hitting cavalry dragon. Her weapon is Frostbite Breath, which as long as she's above 25% HP she will inflict -5 to all of the enemy's stats during combat, in addition to the usual dragon fare of targeting the weaker stat of your ranged units. She also has Swift Sparrow 2 and Lull Atk/Spd to secure her Spd advantage, and Joint Drive Res to equalize her defensive stats; her statline on the highest difficulty is 63/62/51/35/30, which with her skills becomes a functional 63/67/59/43/42 that negates your Atk/Spd buffs and gains another Atk/Spd+4 if she initiates. Unless her victim has a form of follow-up denial, Nifl will devastate anything that isn't a stacked green tank if she hits first, and her strong Spd game makes it difficult to double her yourself. Even worse, Frostbite Breath has another effect: if inflicts [Counter Disrupt] over two spaces from the target if Nifl lands a hit, which means you can't retaliate against her allies (or her, if she survives your attack and hits back that round, which is a death sentence). Speaking of her randomly-generated allies, she starts sandwiched between all of them (which incidentally gives them and Nifl the benefit of her Joint Drive Res), which means even if one of your units can One-Hit Kill Nifl, they're in range of everyone else.
• Pirate Surtr of the "Ice & Flame 2" Tempest Trials+ is an extremely brutal boss. First of all, his Sea-Sear Lance has him inflict -6 Atk/Def on the foe during combat and have the first attack that is thrown at him (or if the foe has at least 75% HP if he attacks) be reduced by 75% if his foe can perform a follow-up attack, which, considering his low Spd of 17 on Lunatic 35 and 18 on Lunatic 40, is very easy for his weapon to meet. He also has Crafty Fighter 3 to guarantee a follow-up attack if he has 25% HP or above at the start of combat and his foe initiates combat and Def/Res Ideal 4 to give him +7 Def/Res during combat if he either is at full HP at the start of combat or has a [Bonus] applied to him, and gives him an additional +2 Def/Res during combat if both conditions are met. Sea-Sear Lance also accelerate his Special Trigger to fire his Bonfire faster, which works on his absurdly massive Def, and thanks to Crafty Fighter also decelerating his foe's special buildup if they initiate combat, activating specials against him will not be an easy feat. Most attacks thrown at him will do very little damage, and only the strongest of Greens are able to really put a dent on him. Thankfully he doesn't have his original counterpart's Sinmara and his playable version's Surtr's Portent, but even then, he's really tough as a boss.
• Ascended Laegjarn from the "Ice & Flame Finale" Tempest Trials+, following her father's footsteps. She has a ridiculous stat spread with 52/39/41/30/18 on Lunatic 35 and 64/43/45/33/20 on Lunatic 40, as well as her entire skill kit from her playable version, which is bad news, as it includes Moonbow, Swift Sparrow 3 and A/D Far Trace 3, and the problematic Flame of Múspell and Rouse Atk/Spd 4. Her Flame of Múspell gives her -1 maximum special cooldown, and if she has a [Bonus] applied to her, it gives her +6 Atk/Spd as well as Atk/Spd/Def/Res equal to half the total sum of field stat buffs she and her foe has during combat, up to +12, and if that total is 10 or more she ignores skills that deny any of her follow-up attacks, so skills such as Bowbreaker or Wary Fighter won't work against her, and Rouse Atk/Spd 4 gives her +6 Atk/Spd and the [Null Panic] status if she is not adjacent to an ally, and she does not start off next to any of her allies on the final map, which means not only will it already give her +6 Atk/Spd/Def/Res but it will also activate the ignoring skills that prevent her follow-up attacks and makes her immune to [Panic], and that's not going accounting her other skills. So from the get-go on Lunatic 35 she will have 74 Atk, 60 Spd, 39 Def and 27 Res, and on Lunatic 40 she will have 78 Atk, 64 Spd, 42 Def and 29 Res, making it nearly impossible to take down in one round of combat. Finally, she is within range of one of your units right at the start of the map, which means you are pressured to either engage her allies first or stand your ground, and considering her high mobility, she will chase your down. What's even worse is that she is deployed with four other Infantry, two of them being Melee and the other two being Ranged, with one of the Melee units being directly between your units and her, and that's not accounting what other randomly generated skills they could have as well, which sometimes includes Rally skills, meaning that it will bolster her further.
• New Year Duo Dagr & Nótt from the "Togetherness" Tempest Trials+. While a Green Bow Flier, they pack together a deadly skill kit to introduce players to the New Year of 2022 with what can they do. They bring a lot of combat debuffs, with Sun-Twin Wing inflicting -5 Spd/Def on the foe during combat as well as the Null Follow-Up effect if they're at 25% HP or above at the start of combat, Atk/Def Rein 3 to inflict -4 Atk/Def to all foes within 2 spaces of them during combat, and Jötnar Bow giving them -1 maximum special cooldown, [Pathfinder]^note allies that pass through the space of the user can move 1 more space, and inflicts -5 Atk/Spd/Def on the foe during combat as well as additional debuffs to their foe's Atk/Spd/Def equal to each field stat buffs they have on their Atk/Spd/Def if they either initiate combat or is within 2 spaces of an ally. So right from the start they inflict -9 Atk, -10 Spd and -14 Def on their foe during combat. Combined with their statline being 52/47/46/29/25 on Lunatic 35 and 64/51/50/33/29 on Lunatic 40, combined with their Atk/Spd Push 4, they effectively get 82 Atk, 63 Spd, 38 Def and 34 Res on Lunatic 35, or 86 Atk, 67 Spd, 42 Def and 38 Res on Lunatic 40. Finally, this is before they receive any buffs on their Atk, Spd and/or Def, which means trouble if the melee Cavalry and ranged Infantry next to them bring any buffs to them.
• Valentine Duo Chrom & Male Robin from the "Abiding Love" Tempest Trial+. As a Infantry Red Bow unit, although a Mighty Glacier with 52/48/31/44/29 on Lunatic 35 and 64/51/35/48/32, they will make you think twice. Although they thankfully don't have Close Counter/Salvo and To Change Fate!, they make up for it by having Reposition, Deadeye, Atk/Def Link 3 and Time's Pulse 3. However, what really makes them dangerous is their Destiny's Bow, where it gives them -1 maximum special cooldown, deals effective damage against Armor and Flying units, and if they either initiate combat or is within 2 spaces of an ally they gain +5 Atk/Spd/Def/Res and a guaranteed follow-up attack, all that on their own making them a challenge already by making them Lightning Bruisers, but the most important effect you have to watch out for is that if either they use or are a target for a movement assist skill between turns 1 to 4, they give themselves and that ally -1 special cooldown after movement. Alongside with their Time's Pulse 3, that means they have their Deadeye ready after just using their Reposition, ready to snipe one of your units for good, and with their statline, with everything in their favor, they effectively get 73 Atk, 36 Spd, 55 Def and 34 Res on Lunatic 35, and 76 Atk, 40 Spd, 59 Def and 37 Res on Lunatic 40, and that's not accounting for who their random allies are on the final map, especially those that start next to them, such as Demonic Spiders Regular Shinon and Regular Larcei who really likes to have their special cooldown reduced to instantly activate their specials.
• Rearmed Líf from the "Life & Death 3" Tempest Trials+. Even though he is a Glass Cannon Sword Cavalry, his entire kit makes him more of a Lightning Bruiser, with him having Bonfire, Fury 3, Lull Atk/Def 3 and Atk/Def Menace, and he wields the Arcane Éljúðnir, which gives him -1 maximum special cooldown, and if he is at 25% HP or above at the start of combat he inflicts -6 Atk/Def on the foe during combat, performs a guaranteed follow-up attack, prevents the foe from performing a follow-up attack and inflicts -1 special buildup on the foe per attack. Combined with his statline of 66 HP, 42 Atk, 47 Spd, 25 Def and 28 Res on Lunatic 35 and 82 HP, 47 Atk, 50 Spd, 27 Def and 30 Res on Lunatic 40, Arcane Éljúðnir effectively gives him Omnibreaker, and even if your units have the actual Null Follow-Up skill you still have to contend with his sky high Spd, which not many units can double him naturally in the first place, even on Lunatic 35. So with everything in his favor, he effectively gets 76 Atk, 43 Def and 39 Res on Lunatic 35 and 81 Atk, 45 Def and 42 Res. Finally, this is all alongside him being escorted with other units, that being 1 Melee Infantry, 1 Melee Armor, and 2 Ranged Infantry, so there are some Demonic Spiders you have to contend with as well, most notably the Ascended Heroes.
• New Year Duo Askr & Embla welcomes the new year of 2023 in the "Renewing Gifts" Tempest Trials+ with a lot of pain. While their stats makes them a Mighty Glacier, their weapon and skills makes them more of a Lightning Bruiser who is incredibly tough to take down, with them having Bonfire, Def/Res Finish 4 and Atk/Res Tempo 3, alongside Regular Askr's Opened Domain, and their Duality Vessel. It gives them -1 maximum special cooldown (which means Bonfire is at 2 cooldown), grants +5 Atk/Spd/Def/Res during combat, a guaranteed follow-up attack, inflicts -1 special buildup on the foe, reduces damage taken from attack equal to 20% of their Def, and reduces damage taken from AOE specials by 1.5x the difference between their Def and their foe's Def if they have higher Def, all which activates if they are within 3 spaces of an ally. Already bad enough with their skills and stats at 52/45/19/45/42 at Lunatic 35 and 64/50/20/49/46 at Lunatic 40, where they will reduce damage taken from attacks by 11 on Lunatic 35 and 12 on Lunatic 40 while also firing a 28 power Bonfire on Lunatic 35 and 30 power one on Lunatic 40, but with Opened Domain giving themselves and all allies within 2 spaces of them the [Resonance: Blades]^note +4 Atk/Spd during combat for one turn and [Resonance: Shields]^note +4 Def/Res during combat and allows them to deny any of the foe's follow-up attacks for every first battle on each player and enemy phase for one turn status effects, as well as -1 special cooldown if they are at maximum special cooldown if they are within 2 spaces of an ally that is from a different Fire Emblem title than him at the start of their turn, they need at least one ally that is a different Fire Emblem title than them to trigger it, and with the two foes that spawn next to them being a Melee Cavalry and Ranged Infantry, there is a 4/46 times 1/101 chance, respectively, that both units are from Heroes and do not trigger their Opened Domain^note at the time, the Melee Cavalry units that are randomly generated and are from Heroes are Regular Nifl, Regular Múspell, Regular Ymir, and Fallen Gustav, while the only Ranged Infantry that is randomly generated and is from Heroes is Regular Ylgr. In other words there's a 0.0861% chance that them and their allies do not get the Opened Domain buffs and not setting their Bonfire at 1 cooldown, and even then it's not a cakewalk to even take down all their allies first before going up against them thanks to the level obstructing your units with 4 wall and 1 water tiles to make both approaching and baiting those foes difficult before the New Year Duo joins the fray, and that's not going into who might spawn with them and get the full benefits of their Opened Domain, which has a good chance to spawn some Demonic Spiders that will ruin your run alongside the New Year Duo, who, with everything in their favor, effectively gets 76 Atk, 64 Def and 61 Res on Lunatic 35, and 81 Atk, 68 Def and 65 Res on Lunatic 40. Thankfully, on Hard 30 and below, they don't have Opened Domain, making them much easier to take down as they will have a harder time triggering their Bonfire and they won't have the [Resonance: Blades] and [Resonance: Shields] status effects.
• Young Duo Mark & Lyn, from "Promising Youth" Tempest Trials+, due to combination of inflicting a lot of debuffs and [Sabotage] (inflicts in-combat debuffs equal to highest visible debuff between unit and their allies within two spaces) and [Stall] (reverses effects that increase movement, causing them to reduce it to 1 instead) at range of five, Sabotage A/R and Canto Control. Unless one brings skills such as Harsh Command(+) or Restore to cancel the debuffs, they have effectively 79 Atk and 75 Res and while their Def is only 43, combined with their health it is enough to have them survive and obliterate the offender with a nuclear Iceberg. Oh, and their debuffs are present on every difficulty since they are on their weapon, so even on Hard 30 they're still nasty and will body the Auto-Battle using players. Admittedly, Harsh Command(+) and Restore harshly counter them, but it still requires the player to bring the ability in the first place, and Auto-Battle is not exactly smart about using it.
• Harmonized Nabatan Igrene & Louise from the "Building a Utopia" Tempest Trials+ are a blue bow infantry with insanely powerful damage output from their Glass Cannon stats and base kit. They have Blazing Wind, Flash Sparrow, Spd/Def Tempo 4, and Pulse Up: Blades, all of which are already powerful skills, but what makes them so dangerous is their Sandglass Bow, which gives them -1 Special cooldown, grants -2 Special cooldown count at the start of turn 1, grants the “unit cannot be slowed by terrain” status and +1 movement to themselves and their infantry and armored allies within 2 spaces, and if they initiate combat or are within 2 spaces of an ally, they gain +6 to Atk/Spd during combat, deal damage equal to 15% of their Atk (which includes area-of-effect specials), and when their special triggers, they deal damage equal to X% of their Spd, with X equal to their max Special cooldown count value multiplied by 10 and then added by 10. They are highly likely to get the jump on your units thanks to their extra movement, and if they do so on anyone who doesn't have massive area-of-effect Damage Reduction and/or Vantage, they are as good as dead due to just how much damage they deal from their Blazing Wind special. Anyone adjacent to the unit that they target will also suffer immense damage from Blazing Wind, which can be disastrous for most Far Save tanks. They also start nearby a random 1-range infantry unit, a 2-range infantry unit, and an armored unit, and they will all gain the extra movement buff just to make things more perilous. On Hard 30, they have Swift Sparrow 2, Spd/Def Tempo 3, and Time’s Pulse 3, the latter of which ensures that they will still have their Blazing Wind special fully charged from the word go, and the Leeroy Jenkins nature of the AI under autobattle means that you're going to have to do some Character Select Forcing with either area-of-effect Damage Reduction, Vantage, and/or having your Far Save tank move in a way that keeps them out of Blazing Wind range to mitigate the odds of a Total Party Kill.
• Valentine's Duo Lyon & Eirika from the "Blossoming Bonds" Tempest Trials+ are a green tome cavalier with Mighty Glacier stats, Iceberg, Occultist's Strike, and Incite Atk/Res. Although they don't have their devastating unique A skill, Gray Illusion, their Tender Vessel still makes them an absolute menace to go up against. It gives them -1 special cooldown, Canto (1), and if their HP is 25% or above, they deal damage as combat begins equal to either 20% of their foe’s Atk or 40% of that amount if they have weapon triangle advantage or if their Res is greater than their foe's Res. They also gain +5 to their Atk/Def/Res, an additional bonus to those stats equal to 20% of their Res at the start of their combat, and halve your percentage based Damage Reduction skills. Because of just how much Res they have, chances are that you’re taking the full 40% of your Atk as pre-combat damage, and combined with additional pre-combat damage from Occultist's Strike and them halving your percentage based Damage Reduction skills, this kind of damage output is more than enough to shred most of your units. What's worse is that you cannot trigger HP based Vantage skills from the damage dealt to you as combat begins, meaning that you'll have to ensure that your unit has already taken enough damage for Vantage beforehand. On top of all of that, you have to go up against two 2-range infantries, one 1-range infantry, and one armor, and if that armor is Dedue, Ascended Idunn, Gilliam, or Fallen Anankos, their Near Save skills will make it even tougher to approach and take out this boss, and the same goes with Ascended Fjorm and her Far Save skill. On Hard 30, they have Poison Strike 3 and Rouse Atk/Res 3, the former of which is thankfully a non-issue, but they still have disgustingly powerful damage output from their Tender Vessel alone, and their Canto (1) makes them especially annoying on autobattle mode, as it can let them stay out of your attack range while they kill every last one of your units as they fruitlessly keep trying to move towards them.
• Young Duo Female Robin & Chrom from the "Young Exalt" Tempest Trials+ are a Glass Cannon with Reposition, Flare, Atk/Spd Link 4 and Inf. Null Follow 4 to make them annoying to go against, especially with the two other Infantry units near them at the start of the map, and Fell Wyrmscale giving them +8 Atk/Spd/Def/Res during combat, ignore the foe's field stat buffs during combat, deals damage equal to 15% of their Atk during combat, ignores the foe's non-Special Damage Reduction effects when they trigger their special during combat, and restores 7 HP after combat, all which activates if their HP is at 25% HP or above at the start of combat. While that is fine on their own, their Draconic Pacts are a another matter entirely: it gives them -1 max special cooldown, inflicts -16 Atk/Spd/Def/Res on the foe during combat, reducing it by 2 for each point of their foe's max special cooldown, with a minimum of -8 Atk/Spd/Def/Res during combat, reduces damage taken from the foe's first attacks by 30% and ignores skills that inflicts -X special buildup on them during combat, all which activates if either they initiate combat or are within 2 spaces of an ally, but that's not the problematic part; If either them or an ally uses on them a Rally or Movement Assist skill, they inflict [Hush Spectrum]^note has the one inflicted on them receives -5 Atk/Spd/Def/Res during combat, inflicts +1 special cooldown before the user's first attack if they have an attack special, and grants their foe before the user's first attack -1 special cooldown if the foe has an attack special and the user has -1 max special cooldown on all foes within 3 rows or 3 columns centered on them after movement and gives them -1 special cooldown, and, once per turn, gives them another action. The last part is the most problematic part, not because that they can act again when they use their Reposition, but it also allows them to act again if their ally uses a Rally or Movement Assist on them if they didn't use Reposition, meaning that they have others that can act as dancers for them, like for example Regular Seliph with his Rally Speed or Regular Nino with her Draw Back. It becomes a mad dash to eliminate them and/or their allies before they and their allies can act and take down your units while also staying out of their attack range, especially with their extra action in mind, but that is not an easy feat that to them having 52/49/50/36/26 on Lunatic 35 and 64/53/56/39/28 on Lunatic 40. Even dropping down the difficulty does not prevent their extra actions going off as they only lose Fell Wyrmscale and downgrade to Atk/Spd Link 3 and Inf. Null Follow 3 on Hard 30, and only on the easiest difficulty that they drop their Reposition.

Story Mode and Other Bosses

• Loki, a main story boss and the final boss of the "Loki's Flames" Tempest Trials. She shows off what version 2.0.0 staff wielders are truly capable of in enemy form. She's fast, and with Wrathful Staff built into her weapon, she'll also hit hard. Thanks to being a colorless unit, she's guaranteed to do neutral damage to most of the player's units as well. Her weapon, Thökk, also has a sort of Gravity Ploy effect built in. Any enemy in a cardinal direction of her with 3 less HP than her and wields a ranged weapon will have their movement reduced to 1. Enemies, especially on the higher difficulties, are all but guaranteed to have higher HP than the player's units, meaning she can activate this pretty consistently against the player's ranged units. In her Tempest Trials, she has a skillset that makes her quite a combatant. Brazen Atk/Spd ensures that if she's weakened, she'll hit even harder and be even faster (on top of the high stat inflation she'll have on higher difficulties). Live to Serve means that even if she does get injured, she'll be able to heal herself if she heals her allies. Atk Ploy will easily debuff the Atk of the player's units. Finally, no matter where she's faced, since she is a healer, you'll want to take her down first before she heals the other enemies. And lastly, when you fight her in Chapter 12-5, she gets serious and finally has Dazzling Staff, meaning your units won't be able to counterattack her, and is accompanied by Lewyn (a Game-Breaker Green Mage) and Silvia (a dancer) for good measure.
• Hel in her first appearance is a surprising Difficulty Spike for an early-chapter boss. Her Atk and Spd are very high for this stage of the game, and unlike most Glass Cannon fliers she is quite capable of taking hits with her high Def and her weapon ability: the Hel Scythe reduces her cooldown count, targets the Res stat if her target isn't a tome or staff unit (Res is the lower defensive stat on most melee units), and most importantly allows her to survive a fatal hit from non-tome and non-staff units if she's above 1 HP. Her skillset also doesn't disappoint, having Glimmer to take advantage of the lowered cooldown count (a deadly combination since her 43 Spd can easily let her attack twice) and Dull Close to nullify any map buffs the target has. If you haven't been working with speedy units of your own or units that can outright ignore the Spd stat (ideally someone with a Brave Bow), surviving an attack from Hel is actually very difficult. Fittingly, she becomes an incredible and formidable Final Boss to close out Book III, because in the last chapter, she has Sturdy Impact, making tanking her nigh on impossible. It would be fine just to player phase her then, if it wasn't for the fact that the rest of the map (complete with Duo Ephraim, who will utterly annihilate if not severely injure anyone he initiates against, and Gerik, whose Firesweep Axe+ denies counterattacks) all add to the pressure, and a few reinforcements show up as well.
• Triandra, one of the primary antagonists for Book IV, is a Green Flier that leaves a pretty strong impression for the Book's early chapters in 2-5. Her Flower of Nightmare weapon is pretty good on its own, granting her Atk+3 and applying Def/Res-3 in combat to your units if they're directly across from her, so she doesn't even have to do anything to cause you trouble - and if she does decide to engage you, she has Poison Strike to make it hurt more. But what really makes her difficult is her unique Dance skill, Frightful Dream, which inflicts Guard and -3 to all stats out of combat if she or her Dance target are directly across from your units. This is a very scary skillset given the company she keeps in 2-5, that being a heavy-hitting Blue Fáfnir, tanky Eyvel and speed demon Mareeta, the latter of which has a B skill that reduces damage depending on how much faster she is than her target. And by the way, Triandra has Spd Tactic to make it worse (Mareeta caps at 65 Spd in the Chain Challenge!).
• Freyja, the Big Bad of Book IV, gets her first showdown in Chapter 9, and manages to put her subordinate to shame. She is classed as enemy Beast units, a first for any of the original characters, as well as being Green Cavaliers with increased movement range. They have a meaty 58 Atk and 51 Spd on Lunatic before factoring in the Cavalry Beast transformation effect^*Atk+2 to the base stat, Atk/Def-4 and Anti Follow-Up on enemy during combat if initiating, and their unique weapon effects are Distant Counter and an effect similar to Close Call/Repel^*damage reduction if faster than the enemy, up to 40% minus the movement. Pretty intimidating on its own, but you might be thinking she's still only one enemy... until you re-read this paragraph and realize we're describing the unit using plural pronouns. Yes, you are fighting SEVERAL Freyjas: three are on the map at the start, and each one you kill will cause another to spawn in next turn, and it's a Survival map. Making matters worse is that the Freyjas start this battle accompanied by both versions of Kris, another pair of speed demons with their own version of a damage reduction skill ^*Spurn, which deals +5 damage when their Special activates similar to Wrath, and they can nullify any debuffs they have on themselves, as well as debuff any of your units trying to engage them. They're all far bulkier than they should be if you don't have a drastic Spd advantage, but you need to be pushing the late 50s to even comfortably take any of them on, and you also need to get past Freyja's anti follow up effect. And since Freyja is a Cavalry unit, any of them can box you in with terrifying efficiency if you get stuck fighting off the Krises. Now, just imagine this map in the Chain Challenge mode, where enemy stats are even higher and your team is likely worn down by that point.

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