In the entrance area of Lower GUK, where the dead mobs start, pets get a little confused when fighting the first 5 - 6 mobs. If you target a mob and send your pet, the pet will travel around the map trying to find a path to the target. While swimming in the water and you get attacked - you may as well just stop and die - the pet will go away for up to a min while your getting attacked. Specially tiresome with wizard mobs that root under water.