The Undead
From Earth-928, the reanimated quartet of mutant corpses found in the bioprocessing facility by Graverobber. His powers were able to bring them back to life who used them to obtain revenge from his former boss Haddad fight the X-Men 2099.
The Undead were a collection of slain mutant slaves once experimented and disheveled in part by corporate plutocrat Zail Haddad who had one prior living slave laborer regarded as Garth Simenon alias Graverobber who acquired the ability to reanimate intact corpses such as the pyrokinetic Ember, the steel-morph Russian, the biokinetic athlete Arcadian and the feline-morph Catscratch in their vindictive intentions to seek revenge on Zail Haddad while incurring terrorist attacks on Halo City with the current X-Men 2099 acting as protectorate diplomats on behalf of Morphine Somers with amnesties to Dr. Doom 2099 as the standing president of America through revolutionary take-over.