In X-Men comics, an Omega-level mutant is one of 14 listed characters with an indefinable upper limit to one of their powers. The list was first revealed in House of X #1 (created by Jonathan Hickman, Pepe Larraz, Pepe Larraz, Marte Gracia, and Clayton Cowles), where it proved that Omega-level mutants sorely need protection. They are exceptional resources for Krakoa and the X-Men, and they are capable of incredible feats.
Source：https://www.cbr.com/x-men-that-should-be-omega-level-mutants/
