Drowning orbs in boss arenas

It is extremely frustrating to die repeatedly to drowning orbs during boss fights. Can't get much distance from them in a small arena such as Cold River. 20% exp down.

Plus they stuck around after the completion and harassed me while I was chosing the mod for the next memories in the sequence.

These killed me 5 times and I failed the map. Would not be so bad if they did not stun the insta kill.