Isti-Papa, or "Great Man-Eater," is a giant hulk of muscle and bone, ragged with matted fur and stinking of algae and muck. A beast of murderous temperament, it devours anything in its path. Sometimes it sits on its haunches and scrapes the bark off of trees, using its long tusks and curved claws. Other times it ambushes other animals--deer, elk, even bear-- crushing them with its great weight before it carries them off to be dismembered. Should it come upon a dwelling, it will demolish it and eat whomever it finds inside. The hide of the beast can turn away spears, and even gunshots barely bother it. None are safe in the forests where Isti-Papa rules.
Isti-Papa comes from Creek Indian folklore, but I thought it'd be fun to equate it with one of the odder paleontological reconstructions ever fashioned: Thomas Jefferson's American Incognitum, a carnivorous elephant with downward facing tusks. It was, in point of fact, a Mastodon, but Jefferson wasn't to know that. The Creek stories equate Isti-Papa variously with a bear and an elephant, so I split the difference and threw some Ground Sloth in there as well.