Superman & Batman Generations Iii #2 2003

Superman & Batman Generations III #2, titled "Century 21: Doomsday Minus One," advances the Elseworlds saga where heroes age in real-time. This issue introduces the Super Twins, Supergirl-Red and Supergirl-Blue, the newest inheritors of Superman's legacy, marking their first appearance. They join Knight-wing and the New Gods to confront a mysterious, time-spanning threat that endangers the entire world. This installment is notable for expanding the generational narrative and introducing key new characters to the timeline.