What is it about Hypersonic Assault

What is it about Hypersonic Assault that stops the villains from doing damage? 

If it deals damage then that villain can't do damage for a round. It's tachyons tied for 2nd most powerful card

I think it hurts their ears so much that they have to spend time recovering/adjusting to the noise.

Like I imagine Ground Pound knocks villains off of their feet, and they need to spend the next round getting back up...With Hypersonic Assault, I imagine villains spending one round with their hands clasped over their ears, unable to do anything else.

Maybe as it's hypersonic it creates a sonic boom and the force of that disrupts the villains (knocking them over, deafening them, etc)? I don't know what would happen if a sonic boom went off in your face but surely it's not very comfortable ;).

Welcome to the forums!

This one.  Basically she's a human flash-bang.

Ambuscade's sonic mine presumably works on the same principle.

If it’s hypersonic, then it DEFINITELY creates a sonic boom. And that shock wave will do more than deafen the villains, it will probably knock them off their feet completely. The art is exactly right, Tachyon is going to bowl everyone over.

Incidentally, the same thing will put fires out. It’s been done in the lab, validating Blinding Speed! (Minor warning, there is a curse word in that url address. But there’s nothing wrong with the content, and the video is super cool!)

Those are 2 really great points. Thanks everyone.