YMMV / Avengers Forever

• Harsher in Hindsight:
  • Immortus's efforts to prevent the existence of the sons of the Scarlet Witch, which would lead to a reality warper rocking the cosmos, was based in storylines from the West Coast Avengers, where she was acknowledged as the "Nexus Being". But reading it nowadays, it gets a whole new significance after Avengers Disassembled and House of M. And even more so after Young Avengers.
  • In the glimpse of the future, Songbird's Avengers team has Jack of Hearts in it. In the normal continuity, the actual Jack of Hearts died quite suddenly in 2003, during Geoff Johns' run on the title. And then there's the stuff about Genis' future, given his own ignominious end.
  • Glimpsing the T'Challa of the Bad Future, Rick Jones is astonished he's now willing to kill. A few years on, after Christopher Priest's character-defining run on the character, T'Challa became characterized as far more willing to do so if he feels it's necessary.
• Heartwarming in Hindsight: Songbird and Captain Marvel came from a future where both of them were Avengers, and more than that, they were lovers. So far, they’ve never been Avengers on the same team at the same time, but Captain Marvel joined the Thunderbolts instead and had a lot of Unresolved Sexual Tension with Songbird. As Immortus would say, destiny does not like to be thwarted.
• Hilarious in Hindsight: And mixed with Heartwarming and Harsher in one go, right at the climax, Cap considers using the Forever Crystal to rewrite history to save Bucky, but refuses due to the temptation of the crystal's power. Fortunately for Bucky, in 2005 it turned out Cap wouldn't have to bother...but maybe if he had, Bucky wouldn't have spent the next several decades as a brainwashed cyborg assassin.
• Memetic Mutation: Years later, Marvel continuity buffs are still blaming Space Phantoms for various continuity errors.
• Salvaged Story: This story did a lot of damage control for the infamous aspects from The Crossing: namely retconning it was actually Kang's future self, Immortus, who manipulated Iron Man; it only went back as far Operation: Galactic Storm (and explaining away a lot of Tony's jackassery throughout the story and his murder boner for the Supreme Intelligence at the end of it); and that the "Mantis" seen in that story was really a Space Phantom posing as her.
• The Woobie:
  • Captain America. This particular Captain America was plucked from time right after the ending of the "Secret Empire" story, where Captain America followed the leader of a terrorist organization to the White House, where he unmasked himself and revealed to be a top-level US officer (definitely not Nixon), planning a coup d'état, and who committed suicide before being captured. This story, written in 1970s by Steve Englehart, left him completely demoralized, and resigned as Captain America shortly afterwards (the Captain America of Avengers Forever had not decided this yet). Well...Kurt Busiek thinks that Englehart's Captain America had not suffered enough. He made him leave Kang's soldiers to their deaths, he sent him to a post-apocalyptic future, he makes him realize that the human race is the most dangerous species in the cosmos, he has to hear things that would happen in his future (such as the US government dismantling the Vision, Iron Man committing murder and framing Hawkeye, etc), a Bad Future with the Avengers turned into a conquering army, a chance to erase Hitler from existence, and so on, and so on...let's just say that, in any other story, if some alien ships begin to fire to the Avengers, he would raise his shield and head to the battle crying out loud "AVENGERS, ASSEMBLE!". Here, he hides in some ruins, unsure of what to do. It's established at the end of the story that this version of Cap was chosen precisely because he'd hesitate; with hindsight, Libra sees that Cap's presence brought unity to the gathered Avengers, but if he'd come from any other point in his history he would have imposed his own control on the group and deprived them of the flexibility they needed to win.
  • Genis-Vell gets it pretty bad too. As a Captain Marvel from the furthest future of all the Avengers chosen, he knows how the Destiny War is supposed to happen and desperately wants to avoid certain events. He engineers a scheme to avoid molecularly bonding with Rick Jones so he can live the life he wants to with Songbird but it all falls apart when Rick leaves the time-defying Sphinx to try and contact the Supreme Intelligence and Kang to help the Avengers out. Rick leaving the Sphinx potentially leads to a future timeline where a descendant of his, Jonz Rickard, leading humanity to conquer the universe with the power of the Destiny Force which sets off the Time-Keepers to try and erase all timelines that are a threat to them thus Genis’ scheme fails. Despite Genis accepting his fate, he nonetheless ends up giving up his freedom and bonds with Rick Jones which leads to the Genis-Vell of the present becoming bonded to Rick Jones.
  • Adding onto this, Genis’ attempt to safeguard the future fails anyway. Despite bonding with Rick Jones as he was supposed to, he marries Songbird and has two children with her, one of whom dies with Songbird. The surviving son, Ely-Vell, grows up seeing the Genis-Vell of the future grow old and weak and unable to fend off an alien invasion due to crippling depression. Despite the Genis of the present helping to defeat the aliens once and for all, the future Genis dies after defusing with his present self while Ely grows more detached towards his father. That estrangement leads to Ely bonding with The Magus and becoming a genocidal monster that destroys entire solar systems to try and free his new master from his interdimensional prison while all of humanity dies and the Earth becomes little more than a massive desert. In order to stop this future from happening, the present Genis resolves to kill Ely in his crib which the future Genis is forced to carry out tearfully.

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