* Trisha Cappelletti from ''WebAnimation/TheMostPopularGirlsInSchool'', is normally sweet, but if you hurt her friends, prepare for shit to go down. Poor Ashley Katchadourian [[spoiler: and Shay van Buren]] learned this the hard way.
* Yumeria in ''Card Players''. There's obviously a reason [[spoiler: she carries a gun everywhere she goes.]]
* Shandala in ''BrokenSaints''. Can you say terrifying, kiddies?
* Flippy of ''HappyTreeFriends''. Dear God.[[labelnote:Background]]Flippy is arguably, the nicest character in the series, but he's also a [[ShellShockedVeteran former soldier]] who is so deeply broken by his experience that even the slightest ''hint'' of something that reminds him of war and/or violence causes him to turn into [[SplitPersonality Fliqpy]], an OmnicidalManiac of a character whose only goal is to ''kill everyone else'' in the episode, usually in graphic and incredibly violent ways.[[/labelnote]]
* Steve the Pirhana Plant in TheMovie of BowsersKingdom. [[labelnote:Why]]After Hal insulted him one too many times, Steve told Bowser they had betrayed him, setting the events of the movie in action.[[/labelnote]]
* In ''Machinima/RedVsBlue'', Sheila is pretty nice and even-tempered, especially in comparison to the rest of the cast. She's also the installed AI in a ''tank''.
** Another AI example is Delta. Mostly emotionless, he's nonetheless shown subtle and very touching dedication to his partner York, even insisting on staying beside him into death. He's later revived, and partnered with South Dakota, who proceeds to try using him as bait to let herself escape. When South is captured, it's Delta that recommends that she [[NoNonsenseNemesis not be given further opportunity for betrayals]].
** Caboose is another example. He started out as an idiot and only [[{{Flanderization}} got]] [[TheDitz dumber]]. However, he is by far the nicest member of the main cast; he cares more about making friends than fighting (unfortunately, when he does fight, generally he's a danger to his allies). However, when he worked himself up into a fury, aside from launching into a series of nonsensical one-liners ("Your toast has been burnt and no amount of scraping will remove the black parts!"), he defeated two armies of flag-obsessed zealots. And later quite a number of [[spoiler:Texbots]] all on his own.
*** [[FridgeLogic His nonsensical one-liners are actually helping him fight,]] because he's saying things that make him angry, prolonging his UnstoppableRage. YouFightLikeACow probably makes the slaughter easier for him.
*** Don't forget that his SuperPoweredEvilSide is caused by him imprinting an evil AI.
** Doc was also a case while he was stuck with O'Malley for a while.
*** After spending most of Seasons 11 through 13 in an alternate dimension, he develops a split personality manifesting as O'Malley again. During [[spoiler:their final stand against Charon soldiers]] he responds to Donut by saying "Aww that's so sweet" followed swiftly by "Now let us strike fear into the hearts of our enemies!" and an evil laugh.
** The [[OriginsEpisode flashback subplot]] in Seasons 9 and 10 shows that Washington was pretty meek for a Freelancer, contrasting with his later [[TheStoic personality]] and [[IDidWhatIHadToDo actions]].
** Add North Dakota to the list as well. He's easily the nicest and friendliest of the Freelancers, to the point where he got the AI he did specifically because he has a nurturing personality and is the TeamMom. But he's still one of the top Freelancers, capable of mowing down an army of Mooks and expertly dual-wielding ''sniper rifles''.
* Shao Kahn of {{WebAnimation/Morty Kombat}} is a rare, villainous example, with a [[AffablyEvil very nice exterior]], and a very mean, dark side.
* [[BravestWarriors Catbug]] is [[RidiculouslyCuteCritter adorable]], [[CheerfulChild innocent]] and loves to play with anyone and everyone. He also shaved Danny's eyebrows (and possibly Chris' hair, too) upon acquiring an electric razor in "Browser Fail", and was revealed to have [[spoiler:killed Jelly Kid]] upon their first meeting in "Jelly Kid Forever". (To be fair, he *is* part-cat, and happily justified his actions as being a present for Danny...like any cat would.)
** Oh, and he's also an EvilOverlord in more than one AlternateUniverse. Yet somehow still adorable.
* ''WebAnimation/{{RWBY}}'' takes place at a military school in a WorldOfBadass, so any 'nice' character probably fits this trope. Special mention goes to [[TheAce Pyrrha]], who [[EstablishingCharacterMoment introduces herself]] by saving a total stranger from plummeting to his death with her excellent spear-throwing skills and power over magnetism.
** ''[[DorkKnight Jaune]]''. In Volume 1, an Ursa attacked the {{Jerkass}} who was bullying him, so he ran at it and ended up [[OffWithHisHead decapitating it]], and then topped it by turning around to the utterly gobsmacked bully and sternly telling him to leave his friends alone. [[spoiler:In the season finale of Volume 2, an even bigger Ursa attacks him, and ''[[CurbStompBattle he slices it to ribbons]]''.]]
* In ''WebAnimation/DeathBattle'', between two combatants, if one of them is nice and the other pretty much isn't, the nice one usually ends up winning.
** [[WesternAnimation/MyLittlePonyFriendshipIsMagic Rainbow Dash]] ''only'' attacks [[Franchise/TransformersGeneration1 Starscream]] when he threatens to kill her, [[spoiler:then delivers a [[CurbStompBattle thorough beating]]. Then, she '''[[YourSoulIsMine eats]]''' his [[OurSoulsAreDifferent Spark]]!]]
** [[VideoGame/YoshisIsland Yoshi]] is described in the intro as a "cute, happy dinosaur". [[spoiler:His fight with [[VideoGame/KillerInstinct Riptor]] ends with him throwing the ferocious fighter over a cliff, after drenching the latter's face [[HoistByHIsOwnPetard in his own acid]].]]
*** This one is particularly notable as for most of the fight, Yoshi just stands there getting beat up.
** [[Franchise/SuperMarioBros Princess Peach]], the somewhat ditsy, happy-go-lucky girl who can't take ten steps without getting kidnapped, [[spoiler:kicks [[Franchise/TheLegendOfZelda Zelda's]] face so hard [[YourHeadAsplode her head explodes]].]]
** And then there's the loud-mouthed, fun-loving {{Spider-Man}} [[spoiler:slingshot-kicking Franchise/{{Batman}}'s torso off?]]
** [[Anime/DragonBallZ Goku]] vs. Franchise/{{Superman}} is a battle between two incredibly friendly and kind, not to mention incredibly powerful beings. Goku is noted as being a family man outside his fights, and Superman is... well, Superman. [[spoiler:Their clash results in the utter destruction of the Earth, and it's implied Superman was ''still'' holding back tremendously]].
** [[WebAnimation/{{RWBY}} Yang Xiao Long]] is, BloodKnight tendencies aside, a laid-back teenage girl who's fond of puns and a joy to hang out with. [[spoiler:She also brutally kills Tifa via {{Recoil Boost}}ed NeckSnap after Tifa cut her head and [[BerserkButton worse]] rips a lock out of her prized blonde mane]].