Tikal
Which piece becomes the temple guard, and what happens to your other figures on that hexagon?
The rulebook has one figure placed as the guard and every other figure of that colour removed from the game.
Any one of your figures on the hexagon can become the guard, a worker or the expedition leader. All other figures of your colour on that hexagon are removed from the game, not returned to supply, so the leader is lost unless he is the one kept as guard. Other players' figures stay.