[Ulzgoroth]

Some rare and generally exceptional animals, such as the more-accomplished man-eating tigers, probably could offer a credible threat to modestly-heroic PCs.

A realistic predator attacking humans effectively almost certainly relies on stealth and surprise. A tiger doesn't need impressive combat skills to take a human down quickly in close combat - but to do so more than once or twice it needs to get the drop on them without anybody else catching it in the act. Stealth, perception, and smart if specialized tactics. It's a furry assassin, not a frontal attack...


(And of course, large herbivores like elephants, hippos, and cape buffalo can easily be deadly to a human who fails to arrange to win the fight before it gets started - but are not too likely to launch an unprovoked attack of their own. Probably. Don't casually get close to hippos or cape buffalo though.)