It's the conclusion to Zero Hour!

From The Adventures of Alpha Centurion #518, Superman in Action Comics #703, Zero Hour: Crisis In Time #2-0, and THE REST!

The rest being: Legion '94 #70, Team Titans #24, Green Arrow #90, Guy Gardner Warrior #24, Legion of Superheroes #61, Justice League America #92, Justice League Task Force #16, Justice League International #68, Robin #10, Catwoman #14, Anima #7, Showcase '94 #10, and Damage #6! All covered in under 2 hours!