Wolves and mountain lions share a lot of the same territory. Fights between the two animals are rare. With wolves usually traveling in packs, mountain lions avoid the confrontations over food.
In this video, a Canadian camper spotted a wolf on top of a mountain lion in what turned out to be a fight to the death. The mountain lion got the upper hand and started bitting the wolves’ neck. The mountain lion breaks the wolves’ neck and holds it till the breathing stopped.