Delwin Florian, code name Negator, has the ability to suppress other people's mutant powers. He's a scrawny little twerp with a whiny voice. Tansy utilizes him to gain a good night's sleep whilst battling Jinn. When he tries to suppress Tennyo's powers, he discovers that Tennyo is actually something that terrifies him so much he can't remember anything that happened. That episode also left him with a broken arm, courtesy of Buster.
The strongest mutants can get a hint of signal through, the barest edge of their power. Everyone else, even exemplars, they’re simply shut down. He has no effect on magic. Devisor gadgets still work. Avatars are unaffected. But mutant powers are stopped cold.”