When Kulan Gath cast the Master Spell over Manhattan, all things, living and inanimate, that were with-in the dome created by the spell were altered to appear as if they were in the ancient past. Those trapped in the dome, and those who entered the dome had their memories erased and replaced. Even the language they spoke was changed. Leaving the dome returned one's memories and appearance to normal, but memories of inside the dome were retained. Those with magic powers resisted the spell to a degree, and Spider-Man was completely immune to the effects of the spell for an unexplained reason.

Gath planned on using blood sacrifices to expand the domes range to cover the entire world, but was stopped by the Avengers and X-Men. With the help of Magik, Dr. Strange was able to revert time back to the moment before the spell was cast.