Reading about the red forest, which I'd never seen, I decided to give the Infinite Black another go. I had reached the sprite and tail village previously just in covering the full map, but figured it would be easier to further explore than Figure Space. I managed to get further.
I found a passage under the village that eventually led to a lava-heavy area, which stumped me briefly after I hit a white switch which seemed to do nothing other than cause a visible earthquake (but acc. to my map that opened no passages out of the main area and I've revealed the map entirely otherwise so anything else would be unnecessary). I then found another hidden passageway that led me into a rectangular room that is apparently a dead end. I bounced and climbed it throughly and could find no other exit.