Particle Field (3.5e Spell)
From D&D Wiki
|Casting time:||1 round|
|Area:||15 foot radius / cubic foot of attuned sand used|
|Saving Throw:||See text|
You spread your sand out into a cloud of dust, almost invisible to the naked eye. A DC 15 Spot check will notice the cloud.
Any creature of Tiny size or larger will disturb the dust to a degree that you can sense their presence. Creatures of smaller size must make a Dexterity check with a DC equal to 10 + technician level for each 10' moved through the cloud or stir up enough of the particles to alert the sandbender. Any creature smaller than Tiny that runs through the cloud automatically alerts the sandbender.
For each cubic foot of attuned sand used in the technique increases the radius of the cloud by 15 feet.