[[Franchise/{{Halo}} A lost war hero]]. [[TabletopGame/{{Warhammer 40000}} A dying god]]. A RagtagBunchOfMisfits [[Franchise/MassEffect on a mission to save the Galaxy]]. What do they all have in common?

All of them have ended up in [[WesternAnimation/MyLittlePonyFriendshipIsMagic Equestria]], and their enemies are right on their tails.

''Peace and Isolation'' is a MegaCrossover written by [=McKnight93=]. It can be found [[http://www.fanfiction.net/s/8498486/1/Peace-and-Isolation.html here]] or [[http://www.fimfiction.net/story/61878/peace-and-isolation.html here]]

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!! This Fanfic contains examples of:

* ChainsawGood: Pinkie certainly thinks so.
* CoolTeacher: N'tho towards Spike.
* CoolVersusAwesome: The Imperium, UNSC (And former Covenant Races), Citadel Races, and ponies vs Reapers, the Flood, and Chaos. WordOfGod has hinted that other factions within the univserses may get involved as well.
** The orks and Dark Eldar have gotten involved as of the latest chapter.
* DarkSecret: While it's not a straight example, Celestia and Luna's interactions with the Emperor are treated as such.
* [[EarthIsTheCenterOfTheUniverse Equestria is the Center of the Multiverse]]: Equestria is linked to all three universes; should it fall, whoever controls it can easily attack the other universes.
* HeelFaceTurn: Trixie and Gilda.
* HeroicSacrifice: [[spoiler: Jacob Taylor gives his life to allow Bareburn and Little Strongheart time to escape.]]
* InterspeciesRomance: One-sided (maybe; see OhCrap) between Luna and the Emperor.
** Braeburn and Little Strongheart.
* JumpedAtTheCall: The entire Imperium jumps at the chance to bring the Emperor back.
* KilledOffForReal: As per the latest chapter, [[spoiler: Chief Thunderhooves and Jacob Taylor have been KIA.]]
* MetaGuy: Garrus, sort of. As a brony, he has more knowledge of Equestria than most of the other newcommers combined.
* OddFriendship: Fluttershy's relationships with Longinus and Cassius (Space Marine and Brute, respectively).
* OhCrap: The Emperor has this reaction when He relaizes not only does Luna have feelings for him, [[spoiler: He may share those feelings]].
** Pretty much everyone when the ponies bring the newcommers together. The Imperials almost start a war against the UNSC and their allies, and Shepard's team almost shoots the Emperor when He takes over one of the Imperials (His new body is not yet complete and He needed a way to communicate with the outside world), thinking that He's actually Harbinger.
* TeethClenchedTeamwork: All the assembled factions, but especially the Imperium; they were already heasitant to work with the ponies, but the situation becomes even more stenuous when the Citadel Races and UNSC arrive.
* YouMonster: Fluttershy towards Longinus, when the Astartes kills a Timberwolf that looked like it was going to attack her when really [[spoiler: It was asking her to hide it, since it's pack had been killed and it was pregnant]]. Longinus is rather shaken by the experience.
* YourCostumeNeedsWork: No one believes Shepard when he contacts the Citadel Council about his arrival in Equestria, thinking that he used CG and modified [=VIs=] to create Twilight and the Astartes. [[SugarWiki/FunnyMoments Until Pinkie warps reality and walks in to the Council Chambers to give them cupcakes]].
** AlternateUniverse: The Emperor [[spoiler: bitch slaps the entire council!]]
* ZergRush: Namedropped as part of the Ork's tactics.

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