Either you sit on him and grip in the other dps/healer to cleave and stop him on cast. You drop amz on convoke and healer lines it, or you all make sure to have a pillar nearby when he has it ready or when the cd is coming back. There is no good way to make sure he never gets value out of convoke unless you hug pillar all game but then you won’t have any pressure either. Just do big dam as your comp is supposed to and bring enough pressure to win before they do… idk.