The forest thing is pretty easy to achieve by simply having a looping map, and using fog to mask the obvious nature of it.
Have the map be a spheroid, use a lot of trees and underbrush, and put a heavy fog in it prevent players from seeing too far ahead.
I'm actually more worried about the temple of the ancients, because impossible geometry I think its going for only really works in 2D
(case in point)
https://www.youtube.com/watch?v=4SjWZm2MwqM