Very good fight of female grizzly vs caribou

http://www.youtube.com/watch?v=kdTdp7Ep6AM

Polar bear and walrus. Looks like a well fed bear. An emaciated one will often not be able to kill a walrus. Polar bears are the second coolest animal. Just watch some Attenborough docs and you'll see why.

http://www.youtube.com/watch?v=Ob_oD1IsYbE

From Grizzly Man

http://www.youtube.com/watch?v=N7vvkloC-Ac

Wolverine pwns wolf

http://www.youtube.com/watch?v=8Ryzqw6ZPE4

There are a few more but these are the better ones.