Secret Wars #4

As the Cabal and the Thors engaged in combat, Sheriff Strange explained to the new-found survivors from the raft that when he and Doom confronted the Beyonders, they were able to kill them, and while Stephen didn't, Doom took their power for himself and used it to build Battleworld from the remains of the Multiverse. The hammer of the Thor from Higher Avalon starts glowing, meaning he was being called for battle. Shortly after Doom was informed of the conflict against the Cabal, Strange, Morales and the heroes from Earth-616 stepped in and turned the tide of the battle in favor of the Thors.

Doom remained unwilling to take part of the conflict until he saw Mr. Fantastic on the scene, and immediately teleported to Utopolis, and stopped the fray, demanding that the newcomers recognize his authority. Cyclops tried to defeat Doom, but despite having the power of the Phoenix Force, he was killed with little effort. To prevent Doom from prejudicially acting upon the interlopers, Stephen used his magic to teleport them away, scattering them across Battleworld. Doom confronted Strange for disobeying him, and ultimately killed Stephen after he accused him of being afraid of Reed Richards.