Rhulk is not progressing phases when affected by arc abilities. He sits in his kneeling animation after the explosion and shields come back up when the damage phase is over. We were unable to get him to move. We had this happen twice in a row with arc subclasses, then after going to orbit and switching off of arc subclasses, the bug did not happen again. We suspect jolt or some other arc effect is doing this. Attached is a screencap of our view of the boss from the starting area of the boss arena.