The game takes place after, Earthrealm's god of thunder, and, Metropolis' defender, repel invasions from both their worlds. An attack by both Raiden and Superman simultaneously in their separate universes causes the merging of the Mortal Kombat and DC villains, and, resulting in the creation of Dark Kahn, whose mere existence causes the two universes to begin merging; if allowed to continue, it would result in the destruction of both. Characters from both universes begin to fluctuate in power, becoming stronger or weaker. Mortal Kombat vs. DC Universe was developed using ' and is available for the and platforms.