Damage Indicators enables visual damage indicators. You see the health of the last mob your cursor hovers over. If a mob that you have come in contact with has moved over 20 blocks away from you, you will no longer see their damage indicator. This mod does not replace the default boss health feature though, so on mobs like the Ender Dragon and the Wither will have the Damage Indicators health bar along with the default Minecraft one that is placed in the top middle of the screen. To open the Damage Indicators menu, press the " . " (period/full stop) key in game.