On typical settings, not on advanced starts or special mods: I saw a 2800 BC WHEEO(R)N once with Kublai. It's on T30. Condition: You may not abused the AI before. The AI should have decided due to RNG to go to Wheeorn. Of course, this is less noticed in unmodded game. In certain mods, you see a fist next to leader name; that is entering in WHEEON mode.