After countless millennia of searching, the immortal super-scientist Krona is closing in on the solution to the ultimate mystery: what came before the Big Bang, that definitive moment of creation for all that is? Having glimpsed a fraction of the answer once before, Krona will stop at nothing to learn the full truth--including destroying entire universes to discover their hidden secrets!
His next target, however, proves to be more than he bargained for. Challenged by an entity called the Grandmaster, Krona agrees to tie his quest for knowledge to a contest of champions--the Avengers from Grandmaster's realm versus the JLA from Krona's! But even if one team can triumph over the other, will they manage to save their own world--or doom two entire universes to destruction?