I think the fact that you can only shoot in 8 direction, and in the one you are walking, is what makes it very difficult. Best strategy I could find is to position yourself so that the enemy comes in the right direction, then quickly spam the minimum amount required to kill the monster when in range. Despite that could not go very far... You can't flee and there is a lot of monster and not that much ammo
Also can't help but see the opened eyes of the ghost as only one eyes like a cyclop...