Aquatic Breath
(Complete Mage, page 39, DnD 3.5)
[Reserve]
Your reservoir of magic allows you to breathe normally even underwater.
Prerequisite
Ability to cast 3rd-level spells
Benefit
As long as you have a water spell of 3rd level or higher available to cast, you can breathe normally in both air and water. This supernatural quality requires no activation. As a secondary benefit, you gain a +1 competence bonus to your caster level when casting water spells.