Baron Warding

Was just in a game and we had baron warded and could see most of the pit and all of baron. All of a sudden baron goes from full hp to none and shows the dying animation. Yet during that whole time there was no fighting animation nor was his health bar going down. If baron is warded there is no reason for us not to see any of the animations and health if someone is fighting him. Same applies for dragon. I believe if dragon is warded and someone starts to fight him, you see his flight animation at the least.