"Future Tense, Part Two of Three: Prisoner of the Super-Heroes"
Continued from Superboy (1994) #21 and continues in Legionnaires #31.
Superboy gets whisked to the 30th Century by Brainiac 5 to aid in the freeing of Valor from the Stasis Zone. He joins in the Legion of Super-Heroes in a search of a technology archive only to encounter his old foe, the Scavenger.