Worstgen
Sentinel
Oh, that's a difficult question indeed. In my opinion, polar bears are the strongest apex predators on land, with 4 inch thick skin, sharp claws, 1200 PIS and easily weighting more than 1200 lbs. You really need at least a few to kill that beast.
Owl Ki
@God Buggy you would need a good few of them. To guarantee a victory, you would need at least over half a dozen bare minimum.