Wither healing nerf

There should be a way to keep the wither from healing, because if you die when you're really close to killing it, by the time you get back he's healed to full health. I think there should be a way to keep that from happening, like shooting the middle head a few times or something. With its unstoppable healing ability, it is much harder to defeat than the ender dragon, which is supposed to be the hardest boss in the game.