When Heorot channels his beam it goes invisible.
The indicator for his spear hit shows one way but he strikes a totaly different area.
The frozen orb vanishes mid flight but still does damage.
Heorot gets stuck in places then appears on the other side of the room.
Edit 1: after restarting game like 5 times the channel still bugs out and only shows the beginning of its animation but the rest seems to work fine now. he dead btw