Board Thread:General Discussion/@comment-27524978-20160210030742/@comment-27907368-20160504074425

What? The prophecy doesn't read anything about the "Angel" having both SOUL types. It reads that someone who has seen the Surface will return to free the monsters, and the Underground will go empty.

The ambiguity leads the interpretation of "free" up to the audience - free from the Underground, or free from the physical world.