History YMMV / Ultrakill

** The "tink", [[HitStop short pause]] and subsequent explosion when you parry something or explode a Streetcleaner's tank with a coin. On top of giving you a split second to breathe, it's just plain cathartic to hear the game giving in to the [[StuffBlowingUp big booms]]. Sometimes, the most wonderful sound can be no sound at all if you overload the arena with so many explosions and blood splatters that the game can't even handle it.

** The "dink-BOOOM" produced by connecting a charged blast with the Alternate Shotgun, complete with a generous dose of hitstop where the entire game freezes for a good half second just to hammer in the impact of the weapon.

** The "dink-BOOOM" produced by connecting a charged blast with the Alternate Shotgun.

** V2 eventually became to be seen as one as well, with several jokes being thrown about them losing their arm (''twice'', even) and some interpreting them as being a SmallNameBigEgo.

** Gabriel in general is a challenging opponent, but his spear attack is easily the most lethal in his arsenal. He'll teleport directly above V1 and slam into the ground, then throw his spear to cause an explosion. The sheer speed at which he does the ground slam necessitates abusing the invincibility frames from the dash, and the spear throw's hitbox is deceptively large, although the spear can also be parried with careful timing to tear off a huge chunk of his health. His enraged state makes the attack even more lethal by adding another ground slam. Brutal makes it even harder by letting the ground slams able to come from any direction.

** Gabriel in general is a challenging opponent, but his spear attack is easily the most lethal in his arsenal. He'll teleport directly above V1 and slam into the ground, then throw his spear to cause an explosion. The sheer speed at which he does the ground slam necessitates abusing the invincibility frames from the dash, and the spear throw's hitbox is deceptively large. His enraged state makes the attack even more lethal by adding another ground slam.
** Two of [[spoiler: Minos Prime]]'s attacks stand out in particular. The first is his "Judgement" attack, in which he teleports towards V1 and delivers a kick that triggers a massive explosion. While the attack is well-telegraphed, the only way to avoid it is to counter it with a ''very'' precise parry (which most often requires you to be on the ground and standing still), and doing so still allows [[spoiler: Minos]] to pull off another attack at point-blank, which includes his ground slam attack. The other nasty attack is the ludicrously fast homing projectiles he fires, which require a parry or very careful movement to dodge, and are spammed much more in the second half of the fight.
** [[spoiler:Sisyphus Prime]]'s "This will hurt." explosion, will indeed ''hurt''. It has such a large radius that it's basically impossible to dash out of before it goes off, meaning the only way to avoid it is by performing a carefully-timed dash or parrying it, and parrying it requires you to be up close and stops being an option during his phase 2. Oh, and it does half your health bar during a boss fight where the boss can kill you in three hits.

** '''Gabriel''', the FinalBoss of Acts I and II, is generally considered to be an extremely difficult fight, with many players claiming to have had to retry the fight upwards of twenty times. He is fast even by the standards of ''Ultrakill'' bosses; boasts ''two'' HP bars, both of which must be depleted to clear the fight; and his moves can quickly drain the player's health especially at close range. He doesn't give much room to heal, either, as he is aggressive and often teleports to quickly close the distance. After his first health bar is depleted, he gains ''a faster and even more aggressive'' moveset.
** The '''Sisyphean Insurrectionist''', introduced in 4-2, is quite the imposing presence during a fight. Its attacks, while distinct, are hard to dodge, especially with the timing on them varying depending on how far you are from it, and it has limitless range, preventing V1 from leveraging any range advantage. It was so overbearing that it was nerfed not a day after Greed's release, reducing its HP and attack speed; but they still are among the most dangerous enemies in the game, especially when multiple of them show up in Cyber Grind or certain later encounters.
** The '''Minotaur''' from 7-1 is an extremely aggravating and difficult encounter in at ''least'' its first phase, to say nothing of its second. It's easily capable of three or four-shotting V1 as well as [[PlatformBattle knocking them off the moving carts and further damaging them]], and due to being a Demon doesn't release that much blood when being hit, meaning the only way to heal is to wait for some {{Mooks}} to pull up on another cart. This in and of itself is incredibly distracting and aggravating if you keep dying while trying to heal up or getting thrown off the cart, but the Minotaur is also capable of removing some your safe ground to work with, forcing you to multitask and carefully manage dashing between platforms while avoiding the Minotaur's blows. Then when you ''finally'' think you've won, you must face its second phase which while easier in terms of healing is still an incredibly tense and stressful battle as the Minotaur gains much quicker attacks and longer combo strings. It's even worse if you're trying to P-rank the level, as fighting it the intended way by [[MarathonBoss patiently whittling down its health]] will lose you valuable time and style points you can't spare.

** Virtues are almost always one of the highest priority threats when one shows up on the field, as they use highly damaging holy beam strikes that can target V1 from anywhere on the map and through cover, which cover a wide area and have lingering hitboxes to boot. Not so bad normally due to their sedentary natures and relative fragility, but after their introduction, Virtues will always appear backing up significantly more aggressive enemies (with multiple at once being a common occurence in later stages), often tucked away in corners of the arena where they'll rain fire from out of sight while you're struggling to handle the other foes, greatly restricting your movement. On top of that, if you thought you can just ignore it and kill all the other enemies, Virtues will [[TurnsRed permanently enrage]] if left alone for long enough and start leading their attacks to make them more dangerous.
** Mannequins move incredibly fast, are more durable than they look, and tend to swarm you from multiple directions at once due to their ability to cling to walls and ceilings. Offensively, they have a one-two punch that comes out very quickly and has them get right in your face, and homing blue shots like the Mindflayer which aren't bad normally, but can get out of control when multiple Mannequins are sniping you from different points across the room; it's also somewhat hard to tell whether one is going to try and rush you down or snipe you until it actually begins to attack. Parrying either of their attacks can instakill them, but they'll often scuttle to new positions in between attacks, making them harder to hit with parried projectiles or retaliate against. Furthemore, they have a 50% resistance to explosions, making it harder to cull groups of them at once like you would with most swarm-type enemies. To add insult to injury, their tendency to lie flat and the way their body and gibs look alike can make it look like they're dead when they're really just idle or winded, potentially catching you off guard if you assumed you had killed them. On the bright side, if one is clinging to a wall, knockback or damage can knock them down, leaving them temporarily dazed and open to attack, and punching a Mannequin mid-fall will straight-up kill it.