Another fun point:
You can lose an eye simply for attacking that SQUARE. Not even just the unit.
So (my favorite) a trio of human commanders with decent defenses and eye shields can stand down Barbarians. Most of them are completely blinded on the FIRST swing - BEFORE they get to even make their attack roll!
The trick is to make sure they stand together. This trick loses its potency if they separate (less chance to blind the enemy on the first swing AND each commander individually takes more hits, instead of splitting them roughly into thirds).