Acid Fog

Acid Fog
Description: Acid fog creates a billowing mass of misty vapors similar. In addition to slowing creatures down and obscuring sight, this spell's vapours are highly acidic. Each round, starting when you cast the spell, the fog deals 2d6 points of acid damage to creatures and objects within it.

External resources

 * NWNWiki:Acid fog
 * d20 SRD Acid fog