Crystal Tap

Crystal Taps, also known as crystal switches, are colorful octahedral switches that either lower or raise the water level in Wet-Dry World in Super Mario 64 and Super Mario 64 DS. If Mario, Yoshi, Luigi, or Wario touches one, the water will drain or rise to the level of the Crystal Tap. There are seven in all, and they are placed in strategic locations across Wet-Dry World. There are five in the main area and two in the underwater town.

If one of the player characters activates a Crystal Tap in the downtown, there will be no way for him to get back to the main area. He can swim back through the tunnel and reach the other side, but the cage will be far too tall to get over. It is possible, though, to use Luigi's Power Flower ability to turn invisible and get back into the main area.