Undine's Curse

Necromancy [curse, evil]
Level: Artificer * 1, Sorcerer */Wizard * 1, Warlock * 1
Components: V, S
Casting Time: 1 Standard Action
Range: close (25 ft. + 5 ft./2 levels)
Target: one creature
Duration: 1 hour/level
Saving Throw: Will negates
Spell Resistance: yes
  The target loses its body's natural ability to breathe automatically. As long as it remains conscious and is able to take physical actions, it keeps breathing and is able to function normally. If it is ever Unconscious (including sleeping) or unable to take physical actions, it stops breathing, must hold its breath, and might begin to Suffocate. Creatures that do not have to breathe are immune to this spell.