During the Battle of Metropolis at the end of INFINITE CRISIS, two Supermen, Kal-El of Post-COIE Earth and Kal-L of Pre-COIE Earth-Two, easily leveled Doomsday together. The two Supermen did what one Superman couldn't: put down Doomsday with minimal damage to themselves.
What accounted for the huge difference, though?
1). Two Supermen were just that much better than one Superman.
2). Kal-El had grown much stronger since his first encounter with Doomsday..
3). Kal-L brought Pre-COIE Kryptonian strength to the battle, which was more than Doomsday could handle.
Which of these were factors, and which one the biggest factor?
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