Necromancy [Cold]
Level: Cleric 2, Druid 2, Sorcerer 3, Wizard 3
Components: V, S
Casting Time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Area: 30-ft.-radius emanation
Duration: 1 minute/level
Saving Throw: Fortitude negates
Spell Resistance: No
This spell thins the oxygen in the area, causing creatures caught therein to suffer the effects of extreme altitude sickness. Subjects failing their saves take 1 point of damage to all ability scores because of altitude sickness. Characters acclimated to high altitude receive a +4 competence bonus on their saving throws. Creatures that do not breathe are immune to the effects of the spell.
Source: Frostburn, page 105.