Monsters have been appearing on Earth upon falling from the sky. The Avengers fight a reptilian monster in Boston, the X-Men fight a spider monster in London, the Black Panther and Shuri defend Wakanda from a thick-skinned monster, the Guardians of the Galaxy defend Groot from a snake-like monster in Seattle, the Inhumans fight a multi-headed monster in Venice, and the Champions fight a tentacled eye monster in Los Angeles. In Peru, Elsa Bloodstone finds a prophecy that tells of the Monster King whom all monsters fear. The Winter Guard fights monsters in Moscow while Valkyrie and Warrior Woman fight them in Edinburgh while Atlas fights them in Washington, D.C. Medusa and Karnak discover that Kei Kawade is an Inhuman who can summon monsters called Goliathons to help fight the Leviathon invasion. Kei then learns how to use his powers perfectly and manages to defeat the Leviathon Queen with a team of new monsters.