History YMMV / Left4Dead2

** The first two-thirds of the Sugar Mill in "Hard Rain" are mainly comprised of corridors, bends, and tight chokepoints, which are usually back-to-back, to the point you can round the corner and abruptly find a Special Infected eager to spill your blood. Uncommon Worker Infected spawn here and [[KungFuProofMook are immune to the Pipe Bombs and Bile Jars' effects]], and pretty much make hordes more annoying to fight off. However, this level has a nasty gimmick; up to ''fifteen wandering Witches spawn throughout the level.'' In spite of this variant being harder to spook, the tighter level design ensures wandering Witches are easier to accidentally [[MurphysBullet shoot]] and bump into. Unless somebody knows how to fight off the Witches, expect a poor soul to be incapacitated ([[FromBadToWorse or instantly killed in Realism or Expert]]) for every one that gets pissed. Then there is the campaign's only crescendo event, triggered by calling up a slow-moving elevator. The building where said event is set has little cover and is difficult to hold out in, and has two big ledges and a giant gap in the center, which Chargers and Tanks can toss you off for an easy death. Finally, the sugar cane field section shortly before the saferoom has water that slows your movement, rows of sugar canes to obscure your sight, and a potential boss spawn area. Everyone should hope they're in the proper condition to fight a Tank there if that happens!

*** For many new players, running the Screaming Oak rollercoaster midway through "Dark Carnival". Especially if it's a group of four newbies on a Normal difficulty game. Rarely does one make it through if they're new to the game unless there are also experienced players in the team to guide them, since it's a long, winding zombie gauntlet with little room for screwing up and very high potential for a team-wipe from an unluckily-placed Charger. It doesn't help that falling off the tracks means having to backtrack through a huge mass of Infected, making Smokers and Jockeys especially lethal.
*** The crescendo event of "The Barns". Notable because there isn't a large wave of zombies like other crescendo events; rather, it's an ENDLESS OCEAN of zombies that doesn't let up until you get into the safe house and close the door. Also interesting to note that this is the chapter right before the concert finale and is notably harder if you aren't prepared.[[note]]Since the AI Director caps the number of zombies in play, it is recommended to distract the zombies with a pipe bomb or Boomer bile, so stock up on those for this one.[[/note]] A Chainsaw (or any melee weapon, for that matter, though the chainsaw doesn't have an attack delay) is also helpful in this part since you can just mow through the horde.
** "Swamp Fever" is disliked as a whole because there's a lot of water that makes you move slower, [[MarathonLevel the levels go on for far longer than any other official levels in the game]], the mud men's mud [[InterfaceScrew covers your screen]], and its overall level design is generally not as interesting as the other campaigns due to large amount of object and layout repetition in the swampy forest and shantytown areas. The finale has you fight two Tanks at once. Combined with the narrow terrain, staying out of the Tanks' reach is incredibly difficult, and this finale will usually result in at least one death even on successful attempts.
** The Sugar Mill in "Hard Rain", where up to ''twenty'' Witches can spawn. This is largely SchmuckBait, as the witches are the "wandering" type and are harder to spook... but even with experienced players, a shot can go wild.

** The pitchfork is just as bad due to lacking splash damage ''entirely''. The only attack is thrusting the weapon forward, which completely ignores any zombies that are only a bit left or right from the central strike spot.

** And in most every campaign that has been ported over from ''1'' to ''2'', there are alterations to increase difficulty. In some cases this is simply to adjust for the new gameplay elements, but they overdo it in some instances, most notably in the Terminal of Dead Air, where what was once a panic event was upgraded to a Rolling Crescendo. However, the developers did not remove the normal crescendo event at the beginning of the level, resulting in this one having two crescendos, with one being one of the hardest in the game (you have to cover a lot of ground to reach the safe room, unlike in Dark Carnival).

** The knife is much slower than you'd expect such a tiny weapon to be, and for some stupid reason [[https://www.youtube.com/watch?v=aFF_Ey7Hjqw its damage tracer arc droops down the further to the right it goes, making it the most inconsistent weapon to hit enemies with.]] Notably, all of the issues with the weapon were introduced in the Last Stand update, likely as a way of {{nerf}}ing it as previously it was one of the better melee weapons in the game.

* VindicatedByHistory: The game's pre-release reaction was rocky to say the least, and when the infamous boycott campaign died down at launch, people were still divided on certain aspects. Nowadays? The game's considered one of the best sequels (if not shooters in general) of all time, and still enjoys a daily player-base of ten thousand players a day a decade after release thanks to a vibrant and active community. It helps that since around 2015, the game is on sale for very cheap during sales events.

** "Wing and a Prayer" requires you to survive the airliner crescendo in Swamp Fever ''without taking damage''. Said event is one of the lengthier hordes in the game, and the terrain makes it virtually impossible to avoid getting swarmed by zombies from all sides. Oh, and friendly fire ''does count'' as taking damage, even on Easy where it deals no actual damage, meaning that a stray bullet from your teammates while Infected are swarming can void the achievement through no fault of your own. The one saving grace of the achievement is that it's tied to an individual player rather than the entire party, allowing you to cheese it by staying in the safe room until your teammates complete the event, but that's assuming they can get that far with only 3 people.

* VindicatedByHistory: The game's pre-release reaction was rocky to say the least, and when the infamous boycott campaign died down at launch, people were still divided on certain aspects. Nowadays? The game's considered one of the best sequels (if not shooters in general) of all time, and still enjoys a daily player-base of ten thousand players a day a decade after release thanks to a vibrant and active community.

--> '''Rochelle:''' She'll be there when we get back. Also, she's a car. Also, [[{{Squick}} that's just creepy]].

** There's also Ellis and [[CoolCar Jimmy Gibbs Jr.'s Car]]. He gushes ''hard'' over the vehicle and acts sentimental to the point of dedicating a little goodbye speech to it when they have to proceed on foot when they reach the jammed road by Whispering Oaks.

* AnnoyingVideoGameHelper: The survivor AI when it comes to healing. They will do their damn best to keep you going, but ignore anything else occurring at the moment. [[ArtificialStupidity Even if that means stopping you where you're standing, potentially condemning you, them, or some other teammate to death]]. Not to mention how they persistently try to heal you the second your health drops below 30. They adjust their "judgement" a little depending on how much temporary life you have, but not very much [[note]]For some incredibly stupid reason, the AI treats temporary health gained by pills and adrenaline shots as being ''half'' of that of permanent health, which often results in the AI wasting a health kit if they only have temporary health, rather than savoring that temporary health and using a health kit much later. The cvar "sb_temp_health_consider_factor 1.0" can be used to rectify this, but a mod is required to implement this without enabling cheats.[[/note]]. The only way to refuse treatment from them is to pull out a healing item of your own (pills, adrenaline or a medkit).

** "Wing and a Prayer" requires you to survive the airliner crescendo in Swamp Fever ''without taking damage''. Said event is one of the lengthier hordes in the game, and the terrain makes it virtually impossible to avoid getting swarmed by zombies from all sides. The one saving grace of the achievement is that it's tied to an individual player rather than the entire party, allowing you to cheese it by staying in the safe room until your teammates complete the event, but that's assuming they can get that far with only 3 people.

* TierInducedScrappy: AI Ellis is this, since he always grabs the Sniper Rifles on sight. Because the Survivor AI is borrowed from ''Counter-Strike'', they'll always switch to pistols when an enemy gets too close. Since this is a zombie game, the chances of that happening are ''very'' high. Cut to Ellis constantly getting the least kills for not using the Sniper Rifles often enough. In the ported ''[=L4D1=]'' campaigns, Zoey also suffers from this for the exact same reason.

%%(ZCE)* BreatherLevel: The elevator in ''Dead Center'' and the raft in ''Swamp Fever''.

** The Nightstick is easily the least popular melee weapon. While it has the fastest swing rate of any melee weapon, it suffers from an extremely narrow attack range and has iffy hit registration, making it difficult to land hits at the best of times and rendering it nigh-on useless against hordes. [[ArsonMurderAndJaywalking It also deals no dismemberment upon inflicting damage]]. The one advantage it has is being able to kill Tanks faster than most melee weapons (since melee weapons [[PercentDamageAttack take a fixed percentage of the Tank's health with each hit]], and the Nightstick is the fastest-swinging melee weapon), but [[ViolationOfCommonSense you're still trying to kill a Tank with a melee weapon]].

** The knife is much slower than you'd expect such a tiny weapon to be, and for some stupid reason [[https://www.youtube.com/watch?v=aFF_Ey7Hjqw its damage tracer arc droops down the further to the right it goes, making it the most inconsistent weapon to hit enemies with.]]

* AuthorsSavingThrow: For the Japan-exclusive ''Left 4 Dead 2: Survivors'', being the second adaptation from a Valve game released by Taito, the controls are now Nunchuk (as the equivalent of the keyboard) and a mouse, simplifying the previously complicated ''Half-Life 2: Survivor'' controls. The game is also virtually unchanged (apart from addition of time remaining, rental mechanics, removal of blood, gibs, and addition of character customization and additional collectibles) unlike the condensed adaptation of the story of ''Half-Life 2''.

* AngstAversion: Unlike its predecessor, ''Left 4 Dead 2'' seems to embrace the less serious, more fun side of the zombie apocalypse. The characters are more comedic than their ''Left 4 Dead'' counterparts, often quipping and seemingly having fun in the heat of battle. Additionally, the music has shifted away from the more eerie tone it had in the original game, focusing on a more exciting and fun feel instead.

* ParanoiaFuel: The "Last Man on Earth" Mutation. No teammates, no Commons, just you and the myriad Special Infected that may or may not be waiting around the next corner. At least [=NPCs=] will be around to help you.

** The bridge finale of The Parish is the first (and only, for those who didn't play custom campaigns) Gauntlet Finale you're likely to face, and it's a doozy. Unlike in regular finales, zombies come in an almost constant stream, and you have to fight through them all to proceed. There are lots of cars for Tanks to punch your way, and the lack of railings means death by Charger is ''very'' likely. And just when you think you're about to head quickly to rescue, you have to navigate a somewhat-confusing path of concrete barriers... and there's yet another Tank which spawns during this section. Hope you've got a medkit and adrenaline shot on standby.

* HarsherInHindsight: The whole game takes on a rather unsettling new look in light of the [[UsefulNotes/COVID19Pandemic COVID-19 pandemic]].
** The infection is suggested both in-game and in supplementary materials to be some kind of supervirus that mutates frequently, [[https://www.healthline.com/health-news/the-coronavirus-is-mutating-what-we-know-about-the-new-variants making it difficult to pin down and counter]]. Making things worse, CEDA (the in-game organization tasked with containing the infection) attempts to pass the whole thing off as "a flu." [[https://en.wikipedia.org/wiki/COVID-19_misinformation Does that sound familiar?]]
** Graffiti in the later levels of The Parish (as well as The Sacrifice comic) reveal that some survivors can be carriers of the virus and not show any symptoms. Fast forward eleven years and the real world suffered from the COVID-19 outbreak where it too can also be spread by people not showing any symptoms.
** The Midnight Riders' staunch refusal to stop touring in the middle of the apocalypse mirrors negationists who would not stop going out in spite of how easily COVID-19 can be transmitted, which contributed to many countries having a high count of infected and deceased. That it came from a rock band also parallels Music/SmashMouth's infamous Sturgis Rally concert in which virtually no one wore masks or kept their distance (as well as Steve Harwell's "fuck COVID" rant), leading to a high count of infected attendees.

* NightmareFuel: Has [[NightmareFuel/Left4Dead2 its own page]].

** Both "Death Toll" and "Dead Air"'s fourth chapters in ''Left 4 Dead 2'', with the addition of gauntlet crescendos – infinite zombie hordes that only stop if you reach the safe room or die.

* AnnoyingVideoGameHelper: The survivor AI when it comes to healing. They will do their damn best to keep you going, but ignore anything else occurring at the moment. [[ArtificialStupidity Even if that means stopping you where you're standing, potentially condemning you, them, or some other teammate to death]]. Not to mention how they persistently try to heal you the second your health drops below 40 (or 30 in The Last Stand update). They adjust their "judgement" a little depending on how much temporary life you have, but not very much [[note]]For some incredibly stupid reason, the AI treats temporary health gained by pills and adrenaline shots as being ''half'' of that of permanent health, which often results in the AI wasting a health kit if they only have temporary health, rather than savoring that temporary health and using a health kit much later. The cvar "sb_temp_health_consider_factor 1.0" can be used to rectify this, but a mod is required to implement this without enabling cheats.[[/note]]. The only way to refuse treatment from them is to pull out a healing item (pills, adrenaline or your own medkit).

** When the [=L4D1-] survivors became playable, they had very little vocalizations for special items and reactions when being attacked by special infected. Later updates would have the survivors use generic vocalizations for spotting special items would also regain their vocalizations for being attacked by a Hunter and Smoker while recycling other reactions for being hit by Chargers, Jockeys, and Spitters.

** The first person view models of the [=L4D1=] survivors is also broken due to the bone rigging not being done properly. Because the models weren't adjusted, the guns and items clip into the survivor's fingers/hands and their textures look low quality compared to the [=L4D2=] survivors, almost as if Valve simply ported over the old models wholesale and left it at that. [[https://steamuserimages-a.akamaihd.net/ugc/477768837566151920/5FB583FEF4AD8590925702730C4B55DC668C971D/ This screenshot]] shows the difference between the broken arm models and the fixed ones from a mod.

* EvenBetterSequel: The pre-launch was surrounded by controversy, and originally a ConestedSequel...until Valve ported Left 4 Dead 1's entire campaign, letting players choose which maps they wish to play. The game's increased pool of special infected, enhanced gameplay systems, new modes, sheer content and maps, melee combat, and ''massive'' increase in modding capabilities (all supported by Steam Workshop, making and uploading new content a breeze) make it also mechanically superior in every way.