>I was thinking along the lines of "Occular Deterioration." If
>they can enhance it, why can't they screw it up?

It would also be interesting to include with the other 'style'
of muter spells, not the gill growth vs. gill removal, but the
kind like 'decalcify + disrupt bone', where one builds at least
marginally or affects the other.

For example, neurological disruption already has some side effects,
but if their vision were degraded the chance for increased or
multiple vision-related side effects might also come into play.