Two massive bears. The one almost looks like some mythical creature when fully engaged/straining.
Massive bear interrupts/attacks another male bear having, umm, . . . relations. Then the 15-minute fight between them is just . . . terrifying.
This may be disturbing for some to watch. It's just . . . . ferocious.
https://www.youtube.com/watch?feature=shared&v=4a-xR3SmdA8