* CriticalResearchFailure: The comic interchangeably says that Magneto has offset the Earth's axis and its magnetic poles. The Earth's axis has nothing to do with magnetism. And even if they were, all of the results of his actions, including the massive flooding of New York City, couldn't be caused by manipulating either the magnetic polls or the Earth's axis.
* DarknessInducedAudienceApathy: The comic was so ridiculously dark that many readers either swore off the Ultimate continuity or were discouraged from getting into it. It doesn't help that an interlude features a dead pool ([[SelfDemonstrating/{{Deadpool}} not that one]]) suggesting the whole thing is nothing to be concerned about.
* DorkAge: Almost universally agreed to be this for the Ultimate Universe, due to taking DarkerAndEdgier UpToEleven and killing off pretty much 75% of the cast.
* HarsherInHindsight: Blob and Wasp fought against each other in ''Ultimates 3'', and Blob said that he would eat her. It seemed like mere battle bravado at the moment.
* {{Narm}}:
** The random deaths, all gory, become sort of funny after a while.
** One of Wolverine's lines to Magneto during their fight? "I got news for you -- if you're God, then God is dead!"
** Probably the crowner is the moment where Doctor Doom demands to know how the Thing managed to enter ''through an open door''.
* NarmCharm: Captain America showing up with no explanation even from himself to help Thor take on Hela's army of the living dead because [[SoCoolItsAwesome we get to see Captain America and Thor take on Hela's army of the living dead.]]
* NeverLiveItDown: No matter how many good things he writes, Creator/JephLoeb will likely never escape the reputation he gained from this comic.
* OlderThanTheyThink: Magneto's evil plan is to screw with the Earth's magnetic poles? The [[ComicBook/NewXMen last time]] he thought of this, he was under the heavy influence of drugs...which were actually the essence of a sentient bacteria...while apparently not actually being Magneto but a Chinese mutant with a star for a brain. Look, just don't have Magneto mess around with the planet's magnetic poles.
* SignatureScene: [[spoiler:The Blob eating the Wasp, graphically biting flesh out her ribcage while muttering "tastes like chicken" in a graphic splash page]] is the image by which ''Ultimatum'' became notorious and proverbial.
* {{Squick}}: The scene of [[spoiler:Blob eating the Wasp's corpse]].
* TheUntwist: The author of the great flood is only revealed at the end of the first issue. However, the "Road to Ultimatum" comics had already been building that Magneto intended to enact a vengeance against everyone.
* WhatAnIdiot:Once the heroes get to the base, there are two tasks: destroy Magneto's machines, and kill Magneto himself.\\
'''You'd expect:''' That Iron Man, whose suit is made of metal and thus vulnerable to Magneto, would be sent to destroy the machines, and that the awesome power of Hulk would be targeted against Magneto.\\\
'''Instead:''' They do things the other way. Iron Man is controlled by Magneto, who uses him to kill Wolverine, while Hulk is busy elsewhere.