Air Helmet

The Air Helmet is an item, purchsed from the Merman for 5, that can be worn to grant the player unlimited oxygen underwater so long as:
 * They have a piece of Air Tube in their inventory;
 * they are within range of their Air Tube;
 * their Air Tube is connected to an Air Tube Anchor;
 * and the Air Tube Anchor is powered by an Air Pump.