I'm interested!
I'm not any good at riddles (either creating or solving), but as far as challenges/obstacles in general, the GMs could have their own characters on separate teams... then take on the primary GM role for the opposite team. That should keep the feeling of "not knowing what's around the corner".
I'm not any good at riddles (either creating or solving), but as far as challenges/obstacles in general, the GMs could have their own characters on separate teams... then take on the primary GM role for the opposite team. That should keep the feeling of "not knowing what's around the corner".