Regime Superman, in the first game he was considered so unstoppable, that trying to fight him without using kryptonite was practically suicide and he was capable of fighting Wonder Woman, Aquaman and Green Lantern at the same time. In subsequent appearances in comics and games it has become much easier to beat, to the point that a large number of characters have beaten him up without using kryptonite, as Alfred or Wonder Woman.
Taking into account the chronological order, Wonder Woman ended up suffering from this. In the comics she was on the same level as Superman, and she even broke his arm on one occasion. In the video games, however, is made clear that Superman is much more powerful than her, and she is defeated by opponents much weaker than Superman.
Draco in Leather Pants: While this version of Superman is not totally without positive traits, the games and comics firmly establish that by the end, Superman has fallen so far into evil that he is little more than a horrible tyrant Beyond Redemption. Superman is willing to do things like destroy two cities and kill millions just to set an example of what happens when anyone crosses the regime and then plans to invade and conquer another dimension, along with killing a child who was loyal to him and idolized him just because he said that this was going too far. Despite this, there is a significant portion of the fanbase that downplays or completely whitewashes Superman’s horrendous actions and, in some cases, even tries to justify everything he did. This is often combined with Ron the Death Eater involving Batman and co, which leads to some people seeing the Regime as the good guys and the Insurgency as the bad guys when that narrative makes it clear that is not remotely true.
Epileptic Trees: After Dark Nights: Metal introduced the Dark Multiverse, an infinite number of universes born from the fears of the main universe that mostly involve a hero succumbing to the dark side, it's a common fan theory that Injustice is part of the Dark Multiverse, though there is plenty of evidence to suggest otherwise. The biggest piece is that the universes in the Dark Multiverse end up breaking apart after the hero turns evil, while the Injustice universe has lasted for years. Finally jossed in Dark Crisis Big Band, which revealed it's set on Earth-49.
Fan Nickname: Superman from the Injustice universe is often given the nickname "Regime Superman" by fans. This isn't technically completely fan-made as Regime is the title used in the Injustice: Gods Among Us video game to distinguish him from the main universe Superman. Fans have used this to refer to the Injustice universe Superman as a whole.
Fan-Preferred Couple: While there is not a lot of shipping in the fandom, easily the biggest ship is Superman and Batman, despite Superman's canon love interests being Lois and Wonder Woman and Batman's being Catwoman, as well as them being enemies in this continuity. Almost any shipping content for the games will be Superman/Batman focused.
Foe Yay Shipping: Despite the fact that these versions of Superman and Batman are enemies waging war on each other, it is still very popular in the fandom to ship them, mainly due to the fact that they used to have a very similar dynamic to their mainstream counterparts and fans love the potential angst about the dynamic.
Misaimed Fandom: Injustice is used as "proof" that Superman is an easily corruptible hero who only needs one bad day to become a psychopath dictator, this usually ignores that it was a series of circumstances that turned him into what he is, instead of simply being a "bad day", in addition to ignoring the obvious fact that this Superman is an alternate version.
The premise of Injustice (Superman becoming a tyrant after someone close to him dies) actually originated from the Superman: The Animated Series episode "Brave New Metropolis, where an alternate version of Lois was killed by Intergang, though he decides to team up with Luthor instead of them being enemies and the 'original' Lois is able to talk some sense into him after she gets transported to that world. The concept would then be revisited in the Justice League episode "A Better World" where the Justice Lords took over the Earth after the Flash was killed by Lex Luthor, much like how the Regime established their hegemony across the world after Lois Lane was killed and Metropolis was destroyed by a nuclear bomb. Likewise, this isn't the first time that Batman formed a resistance group to oppose Superman. Kingdom Come featured a similar storyline with the Outsiders fighting the Justice League and the Joker murdering Lois as well as getting killed by a prominent superhero, though not by Superman but Magog.
Injustice's story can even be traced back to the 12-issue Marvel Comics miniseries Squadron Supreme which involved a group of Justice League pastiches taking over their Earth under the guise of instituting a one-world government free of crime but gradually became more tyrannical to the point where the Batman expy left the group and formed his own team of superheroes to oppose the Superman Substitute.
