large male bull moose have been known to kill brown/grizzly bears
ram them, knock them over, hooves and pound them with their heads
the bear would win most of the time, but not all the time
a moose's neck is very strong, and he can rip things to shreds with his tines, tear down small trees
plus, the hooves are sharp and deep and they know how to use them
and once down they use their heads (and 1500 lbs) to crush things
but if the bear gets on his back/neck, all over
Famous fighting monkey, Jacco Macacco.
Jacco Macacco was a fighting ape or monkey who was exhibited in monkey-baiting matches at the Westminster Pit in London in the early 1820s. He achieved some measure of fame among the sporting community through his reputed prodigious record of victories against dogs.
On 6 July 1874 the Daily Telegraph published an article, written by James Greenwood, in which he reported on 25 June 1874 to have witnessed a fight between a man and a dog. Greenwood recounted the tale in his 1876 book, Low-Life Deeps, in the chapter called In the Potteries.
The fighter, named 'Brummy', was a middle-aged dwarf about 4.5 feet (1.4 m) tall, with oversized features, and bowed legs. He had apparently agreed to fight the dog for a bet, on his theory that no dog "could lick a man". His "opponent" was a white bulldog named Physic. Held by its guardian, the dog apparently did not bark, but was excited to the point where tears ran from its eyes. The fight, watched by an audience of about 50, occurred at an old inn at Hanley, Staffordshire, in a large guest room, its windows closed and its floor covered in sawdust, with the ring cordoned off by a line.
During the fight Brummy was bitten deeply several times on his arms, and the Bulldog was dealt several heavy blows to the head and ribs. After ten rounds the Bulldog's head was heavily swollen, it had lost two teeth, and one of its eyes was closed. The fight lasted until round eleven when Brummy knocked the dog out.
This story was reported on by the New York Times, which stated that the story is probably false, though noting that the Daily Telegraph insisted on its veracity