Thin Air

(Frostburn, DnD 3.5)

Necromancy[Cold]

Level: ; Cleric 2; Druid 2; Sorcerer/Wizard 3
Components: V, S
Casting Time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Area: 30-ft.-radius emanation
Duration: 1 min./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 (see page 90 of the Dungeon Masters Guide).
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.