DR. EGGMAN AND THE METAL LEGION TAKE ON EARTH! Dr. Eggman and his super-powered Metal Legion are looming unchecked over the Justice League's Earth! It's going to take the combined might of the Justice League, Sonic, and his many friends to challenge the mad doctor's mechanical might! But as their battle rages in space, who is left to stop Lex Luthor and the Legion of Doom?