Worst Rare Monster Mods

What is the worst combination of mods on a rare you have had to fight against?

Mine so far is Act 4 cruel, Kaom's Stronghold with a Ranger. I came upon a rare two headed dog with Life Regen, Energy Shield, and Fast Attacks who was possessed by a Tormented Cannibal. I'd dps and it would be on top of me doing enough damage that I'd have to run and pot. When I'd stop to hit again all the damage I'd done would either have regened or the energy shield would be back up. I'd try to hit it again but it would close the gap so fast I wouldn't be able to do enough damage to out pace the regen.