Air Bubble

This form creates a bubble which can be moved, it's 10-foot-radius cube centered on you. The bubble protects anyone inside of it from normal standing water or rain (but not attacks, see below), and can bu used to walk along a sea floor without needing to swim or worry about water pressure. Creatures inside the bubble can breath normally, and the bubble does not run out of air. 

The bubble is an effect that can be damaged and thus breached. The bubble has AC 5. Any damage to the bubble causes the form to end immediately.

At Higher Levels. When you initiate this form at a higher level, the radius of the bubble increases by 10 feet for each level above 2nd.