Rogue and Parasite have both completely absorbed Superman from his first altercation with Doomsday and neither will explode or die from that. Darwin is himself. All three of them are fighting together as well formed team trusting each other and fighting with common morals, (No killing and protect the people) this includes Parasite.
Doomsday is from Hunter Prey and very angry
Fight take place in downtown Metropolis with no outside interference