Witness the destruction as the Onslaught Saga draws to a shocking conclusion! Using the mutant abilities of his captives to evolve into his final form, the psionic psychopath grows in power every second. But as the Avengers, Fantastic Four and the X-Men clash with his external physical body, Nate Grey and Franklin Richards fight back from within. The tale draws to a close in cataclysmic style as the world's champions unite — but how many will still be standing when the smoke clears?