->What the hell is [the ObviouslyEvil demon] slaughtering us for? '''[[SuddenlyShouting WE ARE THE BAD GUYS!]]"'''
-->-- '''Lilah''' [[VillainousBreakdown having a bad day at the office]], ''Series/{{Angel}}''

->When there is evil in this world that justice cannot defeat, would you taint your hands with evil to defeat evil? Or would you remain steadfast and righteous even if it means surrendering to evil?
-->-- '''Lelouch Lamperouge''', ''Anime/CodeGeass''

->You think that there are the good people and the bad people. You are wrong, of course. There are, always and only, the bad people, but some of them are on opposite sides.
-->-- '''Patrician Havelock Vetinari''' of Ankh-Morpork, ''Discworld/GuardsGuards''

->Sometimes itís like watching a wasp land on a stinging nettle: someoneís going to get stung and you donít care.
-->-- '''Sir Samuel Vimes''' of the [[KnightInSourArmor differently cynical]], ''Discworld/NightWatch''

->'''Cybermen:''' Our technologies are compatible. Cybermen plus Daleks: together, [[WeCanRuleTogether we could upgrade the universe]].\\
'''Dalek Thay''': You propose an [[VillainTeamUp alliance?]]\\
'''Cybermen:''' This is correct.\\
'''Dalek Thay''': Request! Denied!\\
'''Cybermen:''' Hostile elements will be deleted! ''(They open fire... [[ShootingSuperman to no effect]])''\\
'''Dalek Thay''': EXTERMINATE! ''(Effortlessly guns down the pair of Cybermen)''
-->-- ''Series/DoctorWho'', "Doomsday"

->When evil fights evil, good triumphs - usually. In the battle between Vecna and Kas, though, the ultimate victor might have been evil. While the battle destroyed a particularly loathsome empire, it also resulted in the creation of three powerful artifacts.
-->-- ''[[TabletopGame/DungeonsAndDragons Dungeon Master's Guide II]]''

->Only through victory can the galaxy be saved from extermination, so that it can be enslaved, and oppressed, as is proper.
-->-- ''VideoGame/GalacticCivilizations II: Dark Avatar'' intro

->'''[[WebVideo/TheAngryJoeShow Angry Joe]]:''' Sometimes [[TakesOneToKillOne the best way to deal with a madman is to send in another madman...]]\\
'''[[WebVideo/AtopTheFourthWall Linkara]]:''' ''(thinks for a second)'' That is a stupid plan!\\
'''Angry Joe:''' Exactly! A stupid plan for a stupid man!\\
'''Linkara:''' Are you ''high?''
-->-- ''WebVideo/{{Kickassia}}''

->Have you ever heard a foolish old saying that evil can only be conquered by good? It's a lie. Evil can only be conquered by evil.
-->-- '''Welstiel Massing''', ''[[Literature/TheSagaOfTheNobleDead Dhampir]]''

->'''Demon''': You cannot hope to defeat pure evil!\\
'''Slade''': Actually, I'm not such a nice guy myself.
-->-- ''WesternAnimation/TeenTitans''

->'''Yugi:''' Look! Kaiba's dueling Pegasus!\\
'''Joey:''' But they're both villains! Who're we supposed to root for?
-->-- ''WebVideo/YuGiOhTheAbridgedSeries''

->It's a pity they both can't lose.
-->-- '''Henry Kissinger''', on the UsefulNotes/IranIraqWar

->[[MonsterLord Giurescu]] is gone, Stephen. God chose to [[PayEvilUntoEvil cancel evil with evil.]] [[ThoseWackyNazis The Nazis]] took Giurescu, and he cannot come back.
-->--'''Father Nicholas Budenz''', ''Comicbook/{{Hellboy}}: Wake The Devil''

->And so religious nuts will overthrow a government of hypocrites. The situation would be ludicrous if it wasn't actually happening.
-->--'''Guehala Dennis''', ''VideoGame/TheTaleOfAlltynex''

->'''Sploorfix:'''And you still want to spark a war between the Lattrox and Bleen? A war in which millions of innocent, intelligent beings will perish?\\
'''Vexxarr:''' No, no. See, the [[ImAHumanitarian Lattrox]] and [[PlanetLooters Bleen]] would be fighting ''each other''...
-->-- ''Webcomic/{{Vexxarr}}''

->I was the evil that opposed other evil, leaving the good and the meek in the middle to live and inherit the Earth!
-->-- ''Literature/MikeHammer''

->When [[BloodBath blood bathers]] and [[TabletopGame/VampireTheRequiem vampires]] meet, the results are usually violent in the long term: blood bathers, after all, bring trouble in the form of hunters [[note]]who see "drained of blood" as "vampire activity," which is reasonable [[/note]], law enforcement [[note]] which can be problematic for Kindred trying to cover up their activities[[/note]], and scarcity of food [[note]] when people realize there's a killer on the loose, they tend to curtail nighttime activity[[/note]]. Another source of conflict, though is that once a blood bather has completed the Bathing Ritual, the blood becomes inert. It is useless for transfusions or any other medical purpose, and it is useless for any other mystical use - including consumption by a vampire. Once the local undead discover that someone is killing the living, draining their blood ''and'' making that blood useless, they will [[PragmaticVillainy probably find a way to kill the blood bather]]. Or at least, they can try - blood bathers aren't exactly easy to kill.
-->--''[[TabletopGame/NewWorldOfDarkness Immortals]]''