Dragon's Dogma: Dark Arisen

Evil Eyes can only be found in the Everfall (Chamber of Confusion and Chamber of Sorrow) or the Rotunda of Dread on Bitterblack Isle (again, may need to reset it to get the right monster to spawn).

These enemies are much harder than hydras. They are immune to attack unless they themselves are attacking, so when it prepares an eye beam, rush in and take a shot. Once you staggar it, you can get a good deal of damage in. If your mage can use a Holy enchant on your weapons, this helps as well.