* BreatherLevel: The second mission, which is the serial killer's home. At most this only has two (sometimes a random thug suspect are present) suspect compared to a small (but still numerous) arms dealing gang of the first mission.
* CrossesTheLineTwice: In mission 6, elevator doors can keep opening and closing on a victim's head. And if you go back to that area later, it'll still be the case, because there is apparently no way to actually get him out.
** It's an idle enviromental animation. But still... the poor devil...
* EarWorm: The soundtrack of SWAT 4 could be this.
* MemeticMutation: [[MostAnnoyingSound "You're in]] [[ArtificialStupidity my way sir"]].
** "[[WebVideo/TheSpoonyExperiment OH, YOU FOOL!]]"
* MostAnnoyingSound: "You're in my way, sir." "That's ''my'' mark you're at, sir." "You're standing in my spot, sir." "Boss, out of my way." "I need you to move, sir." "Please move out of my way, sir."
** Most of these later became a MemeticMutation since [[WebVideo/TheSpoonyExperiment Spoony's]] let's play on this game.
* PlayerPunch: If you found the game pretty standard before then mission 9, The Children of Tarrone, will clean your clock. Most will be creeped out by the NightmareFuel of a apocalyptic cult and likely finish the level in the basement where they show to be a new breed of evil: murdering their children and burying them in the basement.
* SurprisinglyImprovedSequel / GrowingTheBeard : Definitely the best and most mature of the four ''SWAT'' games so far. It helps that it was in DevelopmentHell for ''six'' long years and that the talented old warhorses at Irrational eventually got the opportunity to work on it.
** Also, the The ExpansionPack is a variation of this trope, since it heavily improved the already great original game further.
* ThatOneLevel: [=DuPlessis=] Diamonds, for how cramped it is, you WILL get shot. Also, the Taronne residence, where lethal weapons will blow up the carelessly scattered explosive hazards and kill anyone in the blast.
** Mt. Threshold is pretty tough as well, it's the largest level in the game, so it can be difficult to keep track of where you've been, and there's about a dozen places where you can get ambushed easily.
*** The solution? Teargas. Lots and lots of teargas.
** The Old Granite Hotel. Not only are there a lot of highly skilled opponents with hostages, you're also on a 10 minute time limit to defuse several bombs. Spoony's playthrough of the level was titled "I die a lot," took several days to film, took over fifty lives, and had to be compressed into a montage.