As iconic heroes of two worlds collide in the Amalgam Universe, Spider-Boy shares a mind-bending adventure in time with the Legion of Galactic Guardians 2099! As the Arach-Kid battles his airborne adversary, the Scalvulture, little does he know his fate hangs perilously in the balance — and all hope of salvation lies a century away with an assemblage of young heroes inspired by his legendary adventures! But can the Legion of Galactic Guardians 2099 avert the doom of their idol without causing complete chronal collapse? Or will their actions only bring it about?!