Inaccurate?

Caustic Mire

(Complete Mage)

Conjuration (Creation)
Level: Sorcerer 4, Wizard 4,
Components: V, S,
Casting Time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Area: 20-ft.-radius spread
Duration: 1 round/level (D)
Saving Throw: None
Spell Resistance: No

A foul sludge seeps out of the ground, coating the area before you.
You cover the ground in an acidic slime, roughly the consistency of thick mud.
The sludge is sticky; entering any square affected by caustic mire costs 2 squares of movement.
In addition, each square entered deals 1d6 points of acid damage to the creature moving.
A creature who stands in the area without moving from its space takes 1d6 points of damage per round at the end of its turn.
The fumes rising out of caustic mire are flammable.
Any effect that deals fire damage within an area of caustic mire deals an extra 1 point of damage per die (minimum +1 damage).