Solid Fog

Creation [Binding]
Circle: Tactician 4
Casting Time: 1 standard action
Range: [Close]
Effect: 40 ft radius spread of dense and physically-hindering fog
Duration: [Encounter]
Saving Throw: Will; see text

This spell functions like obscuring mist, except the spread originates from target square within range, effects that inflict damage with the [Fire] descriptor do not remove squares from its area of effect, and a creature does not have line of effect to another creature or square if one or more squares of the fog exist between the two creatures or creature and square. Additionally, whenever a creature enters or exits a square in the spell's area of effect, it must stop moving. A successful Will save allows the creature to continue moving, but it suffers a penalty equal to half its movement speed to its movement speed for that movement.