No Breath

Most useful of all breathing-related magic, this spell completely frees one subject of the need to breathe. The subject's body sustains itself for the duration on magical energies rather than oxygen. Beyond being able to survive underwater and within areas of silt and smoke, the recipient is immune to poisonous gases, stinking clouds, and similar attacks. This spell is also virtually the only way to travel on the planes of Vacuum, Positive Energy, and Negative Energy barring a potent magical item.

The caster can affect as many different subjects for the spell as he desires, but the duration is then divided up equally among the various recipients.