Shadow Plague

Master/shadow calling
Level/School: 8/conjuration (creation) [cold]
Range: medium (100 ft. + 10 ft./level)
Area: cloud spreads in 20-ft. radius, 20 ft. high
Duration: 1 round/level (D)
Saving Throw: Reflex half; see text
Spell Resistance: no

This mystery functions like the spell incendiary cloud, except that it deals cold damage rather than fire damage.