User blog comment:Srypelican/What got transported the the New World?/@comment-1846146-20151021011807/@comment-27036174-20151021015406

It's not stated outright, but it is said that Zy'tl Q'ae fell out of a hole in the sky along with a lot of other powerful monsters. Therefore it is theorised that they came from YGGDRASIL, which I feel is plausible considering that Zy'tl Q'ae was extremely powerful (around lvl 85).