if Wampa cancels all dice including a crit, does that count as a hit to disable a stealth device?

Considering that Wampa will cancel all of the dice BEFORE the Compare Results step there will be no uncancelled boom/kaboom to cause a hit which means the Stealth Device should remain unharmed. The ship still takes a card but there are way to deal cards and destroy ships without actually hitting them with an attack.

if Wampa cancels all dice including a crit, does that count as a hit to disable a stealth device?

Or for the short version: no.

Thanks guys!

Considering that Wampa will cancel all of the dice BEFORE the Compare Results step...

Wampa's cancellation happens during Compare Results, at the beginning. The conclusion you draw is still correct, however.

Considering that Wampa will cancel all of the dice BEFORE the Compare Results step...

Wampa's cancellation happens during Compare Results, at the beginning. The conclusion you draw is still correct, however.

I guess I'm not drawing a distinction between it happening right before the Compare Results step and happening at the beginning of the CR step. The net effect is ultimately that the attack dice are cancelled before the defense dice get to them and even then when there are no boom/kaboom left that means the attack misses anyway.