This boss is really easy to "cheeze", but hard to take the normal way.

Put your ranged dps and healer under a mushroom, and they will not be lifted into the air by the stalkers tractor beam. It's now just a matter of tank and spank. Might take some aoe now and then, but I found it to be really easy. I have not yet tested The Underbog in heroic (farming the easier ones first like mecha & slave pens for gear upgrades).