Admittedly, there would be times when it would be difficult to determine intent. I would imagine the GM would observe the scene for a while before making any call. If the player seems to be mounting his pet, realizing the monster is attacking into empty space, then leaving and returning to let the monster reset, then maybe the GM doesn't have anything to worry about. However, if a player in the same situation seems to be forcing the monster into the "blind to his attacker" situation and bragging about how no one can stop him from exploiting, then that player may find himself in a little trouble in the near future.

Cynthe
Community Manager
ORIGIN Systems

参照： UO Stratics