This mutant had been sent among an Annex Squad, with two others, the Agent X-13 and a laser-striker mutant, by the authority of Earth-89149 after the first recon force had been destroyed through Forge's efforts. They were looking for realities with less of mutants to defend them, having been affected by the M-Day, in order to annex them for an unknown reason linked to a speculated toxicity of the Ghost Boxes, transdimensional transportation devices.
The two antagonistic teams ended up in Tian where the invaders looked for a power source to charge their Ghost Box. As the city was powered by the Chinese mutant community living there, dead since the M-Day, they couldn't find it, and so Agent X-13 split from the group with the Box.
The X-Men eventually came to Tian and were attacked by the last artificial mutant and the two remaining scouts. While the laser-striker attacked Wolverine and Armor, the inhibitor tried to take down Storm and Emma Frost once their powers were gone, but the two X-Women were trained to battle without powers, and defeated him. Unconscious, his mind was explored by Frost, and used to know the truth during the interrogation of the Chameleon artificial mutant.
Mutant Powers Inhibition: This mutant had the ability to cut off the mutants' abilities, starting with the finest abilities to the more passive.
Mind Shielding: This mutant was able to shield his mind in a certain degree. He wasn't detected by Emma Frost upon the X-Men's arrival on Tian, but was ultimately detected by Emma. Once passed out, his mind was totally open to be read.
He had to maintain a certain amount of concentration for his powers to work: Intense pain could disturb his powers.
- Being from an alternate reality, his mutation differed from mutants on Earth-616 in that his X-Gene was not on the 23rd chromosome, but instead on chromosome 13, explaining the possible immunity of his kind to the effects of M-Day, and his invisibility to Cerebra's detection.
- This mutant's name was never revealed and he was talked about only as "an inhibitor".