Poisonous Cloud

Poisonous cloud creates a bank of fog like that created by fog cloud, except that the vapors are toxic. The cloud deals 1d2 points of Constitution damage per round to living creatures that fail their Fortitude saves.

A creature that succeeds at its save but remains in the cloud must continue to attempt a new saving throw each round on your turn.

Poisonous cloud can be made permanent with a permanency spell cast by a caster of 13th level or higher, at a cost of 12,500 gp. A permanent poisonous cloud dispersed by wind re-forms in 10 minutes.