In Code Gease if your blind your safe, in needless you need to be deaf or hard of hearing.
What if Cruz's ability here is cancel? You know the kid in Xmen movie 3 that can take away cancel the mutant powers, I just have a hunch if ever he'll have a fragment within him, that might be it, that is also a pretty broken power. Just an ordinary human relying on wits and survival to battle, no other techniques or special abilities.