the main weapon in defeating a whole race is (seemingly un-)racist propaganda.

Q: The main weapon to defeats the whole mutants race is?

A: Themselves.

thought we already knew that Scarlet witch was the ultimate Mutant Death Weapon

Cerebro is limited to the user's abilities. While there have been different versions over the years, it seems that to commit massive destruction on a global scale would require an extremely powerful and well-trained telepath which are pretty rare.

any mutant who has a mental breakdown

who do you think could do it? Sinister?

Moondragon?

I'm just trying to think of characters who would have nothing to lose..

I thought it was established that Wanda was the ultimate mutant death weapon.

The main weapon to destroy the mutant race? Poor comic sales.

A Celestial with the ultimate nullifier. Sounds good anyways.

Bring Vulcan back in or have somebody possess Rogue having her take the telepathic abilities of many and then use Cerebro to hurt the mutants

Giant Killer robots seem to do a pretty adequate job of it unless they step up to the X-men's lawn.

Grant Morrison and Frank Quitely

Brian Michael Bendis.

The main weapon to defeat the whole mutant race is... users who make threads like this!