The Chief's Guard (1).
Although the creatures possessed a modicum of intellect, they weren't very smart...
Cain's reasoning told him that the reason for this was the fact that the creatures had no natural enemies. Hence, the only thing they needed to learn how to do, was hunt for food.
Considering how powerful they were in the first place, it wasn't very hard. And because of the fertility of the female counterparts, which, in his own opinion, shouldn't even be possible, they had more than enough numbers to burn through.
However, this is where the confusion began...
'They are at the top of the food chain here. They barely lose any of their numbers when they go out to hunt. The females are also very fertile. Their numbers should have surpassed this...'
Cain had thought about this for a while, but he couldn't come to a logical conclusion. Logic and reasoning told him one thing, but the reality was different.