[Crossover] Batson of the Bat Family II

Summer vacation! Day one! Billy was completely dumbfounded in the secret base. Because whenever he transformed into the superhero Shazam, the Rock of Eternity in his eyes would immediately start to... split apart! The extra, dilapidated Rock of Eternity had its anchor in another world. There was no Shazam there, but once there was Captain Thunder, a fusion of six heroes; There was no Justice League, only the Avengers in its place; The Amazonian tide swept across the world, Atlantis stood ready for battle, and the shattered land caught between them summoned the Storm King from the depths of history! Billy: There's no Batfamily there, either! --Only the solitary Old Bat. The bald mage who invited him across dimensions: This is the call of the legacy. It is inevitable. --The Rock of Eternity in a parallel world desperately needs a new guardian, a new Shazam. ◆ Batson references. Focus on the Batfamily's bonds, with no pairing. ◇ Two universes and a fused setting, featuring elements from DC, the MCU, and FGO. ◆ Billy's familiars: the seventy-two demon pillars from FGO, and their combined form, Gaigai. ◇ A hodgepodge of settings, with timeline adjustments and personal interpretations. For related works, see the previous story. Theme: Take responsibility for your own legacy.