One player must touch the other players, while others run away from him. When the catcher touches any player, has to say "rock" or "tree".
If you tell a tree, the affected player must stand toe feet and wait for another player he stand to lose through the legs.
If you tell a "rock", the affected player must squat down and wait for him until someone jumps. Some pass through the legs, or jumps, the player may continue to run.