The Drop Bear is the carnivorous cousin of the friendly koala of Australia that are known to invade and adapt in other countries. There are two known species in the eastern hemisphere: the Australian and the New Zealand. The Australian, less aggressive then the New Zealand, is the smallest of the species and are more adapted for tree life. The New Zealand, more aggressive, is a medium sized Drop Bear that have adapted for both canopy and ground life. There is only one species of Drop Bear that lives in the western hemisphere: the Giant American Drop Bear. This species is the largest of the species and have adapted for living in mountainous areas (such as the Rockies and the Appalachians).
Being abnormally aggressive than the other two known species, this species will attack anything from humans to larger predators. They're known to attack the largest of grizzlies, wild boars, cougars, elk, deer (mainly bucks), and rarely supernatural predators such as the Sasquatch or the Onza (larger species of feline related to cougar).
Giant American Drop Bears, weighting heavier, are known to either live in large enough trees that can withstand their weight or in caves. Large cave-dwelling animals (mainly bears) must compete for shelter in caves with this large animal. Giant American Drop Bears hibernate during the winter and this is the main reason why bears go into a brutal death-match with this larger predator. Usually the Drop Bear wins which allows the creature to use the body of the bear as food during the freezing months. The only way to kill a Giant American Drop Bear is by using armor-piercing weapons because of their thick fur that keeps the creature warm during cold months.
This photograph above is a human victim of the Giant American Drop Bear who became extremely lucky for escaping its clutches. Normally, this Drop Bear can easily succeed into killing a person.