* AndYouThoughtItWouldFail: Marvel famously had very little confidence in the event, as it was almost entirely made up of characters who had been irrelevant for well over a decade IRL, while almost all of Marvel's A-List was busy with ''ComicBook/CivilWar2006''. Which made it all the more surprising when the event became popular enough to spawn multiple sequels and an ongoing, in the process establishing Marvel Cosmic as a pillar of the Marvel Universe for years to come.
* CompleteMonster:
** [[NamesToRunAwayFromReallyFast Annihilus]] is the BigBad of this Universe-Wide CrisisCrossover, and becomes far more depraved than [[Characters/FantasticFourCentralRoguesGallery any of his previous appearances]]. No longer content with ruling the Negative Zone, Annihilus leads an army of insect monsters out into the galaxy in what is aptly termed The Annihilation Wave. Consuming whole star systems and devouring entire worlds, then using what's left of the population as fuel for his army, Annihilus wipes out numerous races and leaves the Skrulls near-extinct with his genocidal campaign. Annihilus implants numerous innocents with body-controlling bugs that painfully force them to do his bidding and when one of his armadas encounters resistance while invading a world, Annihilus [[BadBoss massacres the entire fleet]] for taking too long to destroy the planet. Capturing [[Characters/MarvelComicsGalactus Galactus]] and many of [[Characters/MarvelComicsHeraldsOfGalactus his Heralds]] after brutally murdering the hero Quasar, Annihilus uses them as superweapons, which leaves them in a near-death state of constant agony, then reveals he plans to use them to [[OmnicidalManiac wipe out all life in the universe and reign over the void that's left]]. Harboring hatred and disgust for everything in the universe that isn't himself, Annihilus is the worst being the Negative Zone has to offer.
** ''Super-Skrull'': [[InsaneAdmiral Admiral Salo]] is the captain of the ''Harvester of Sorrow'', and one of the cruelest members of the omnicidal Annihilation Wave, boasting a record of hundreds of populated planets just to his ship's name. Salo is [[EstablishingCharacterMoment introduced]] vaporizing a [[Characters/MarvelComicsSkrulls Skrull]] planet, refusing to let his own men escape the vicinity of the blast, and attempting to continue on the planet of Zaragz'na. Despite the best efforts of Kl'rt, the Super-Skrull, Salo uses a [[TheMole mole]] to capture the Super-Skrull so Salo can [[ForcedToWatch make him watch]] the destruction of Zaragz'na--a planet Salo knows the Super-Skrull's beloved son is on.
* DiagnosedByTheAudience: Rocket Racoon in the ComicBook/StarLord miniseries has some obsessive-compulsive tendencies. And is asked by Bug, whether or not he has it.
* FirstInstallmentWins: While there had been many [[CrisisCrossover Crisis Crossovers]] after this one in the cosmic Marvel series, fans still agree that ''Annihilation'' is the best yet.
* ItWasHisSled: [[spoiler:Ultron]] is the mastermind behind the Phalanx conquest. He's even on the front cover of the omnibus edition.
* MoralEventHorizon: Annihilus was already a bastard, but this event begins with him destroying the remains of Xandar, killing off all the Nova Corps but Richard Rider, and as it turns out he did this solely to draw out Gabriel the Air-Walker.
* NightmareFuel:
** Richard's temporary insanity after getting the whole Nova Force.
** Quasar's death isn't pretty.
** Bugs, crawling around under your skin, controlling your actions.
** The Phalanx infection first making itself known by wires ''coming out of the eyes''. To say nothing of being enslaved to Ultron's insane will. And you can still be pissed about what's been done to you, while still being brainwashed to think it's the greatest thing ever.
* RescuedFromTheScrappyHeap: This story Is responsible for turning Nova from a [[CListFodder C-list Spider-Man Wannabe]] to a badass and mature hero.
* {{Tearjerker}}:
** The death of Gabriel the Air-Walker.
** Richard waking up only to find Xandar in ruins and that he's the only survivor.
** From Conquest, the [[spoiler: death of Moondragon.]] Extra points for Quasar's reaction.
* TheScrappy: Wraith, despite being one of the main heroes of Conquest, is generally disliked due to his overly edgy look and personality which feel like a reject from MediaNotes/TheDarkAgeOfComicBooks.