After his mate and pups were killed by cattle ranchers in 1911, this wolf took revenge and hit the ranchers where it hurt them the most: their livestock. He never took another mate and was responsible for the death of $25,000 (equivalent to roughly $300,000 in 2016) worth of horses, cattle, and calves. The wolf eluded professional hunters, sportsmen, and bounty hunters alike for 9 years. The government sent a highly experienced federal hunter and it still took that guy seven months to successfully hunt down this animal.