The pitch black panther was a rare beast. It had come in search of food and good materials. Naturally, the butterfly paradise had a tempting scent. But where things had grown perfect for it, was when a group of weaker looking prey had come out of it.
Most beasts would not be able to go in to dungeons like the butterfly paradise. There was a strong lord beast that was in control of it. Naturally, this was a great way to keep beasts from entering the dungeon. But that was not the best thing. Many beasts would stay outside of such places to hunt.
Some of the more powerful butterflies had left the butterfly paradise after hatching from cocoons. Where many people would think that this would be a deterrent of sorts, it was not. The idea that there were stronger beasts escaping a dungeon should have made the local beasts wary of nearing it.
Creation is hard, cheer me up!