Wall of sand

Wall of sand was an arcane evocation spell that created a temporary wall made of spinning sand.

Effects
This spell could create a wall up to high. The thickness and length of the wall were limited by the level of the caster. The largest wall that could be created by a wizard meeting the minimum requirements for this spell was thick and  long. The wall required a solid footing and once its dimensions were set they could not be altered. The wall did not require further concentration by the caster and lasted for one minute per level of the caster, or until the caster dispelled it, whichever came first.

The wall was a swirling mass of sand that was completely opaque but not solid. Open flames engulfed by the wall were immediately extinguished. Movement through the wall was possible at half speed, but while encased in sand, normal creatures could not see, breathe, speak, or cast spells. Creatures requiring respiration began to suffocate after one minute within the wall. Because of the impairment to movement and perception, those emerging from the wall were much easier targets for attack.

The wall of sand was permeable to magic cast through it, but line-of-sight was completely blocked and spells that required seeing the target would fail.

Components
In addition to verbal and somatic components, the material component was a handful of sand.

History
This spell was invented by the famed transmuter Nezram and set down in his book Unique Mageries, which he left behind and never returned to claim. Wall of sand was published in "Volo's Guide to All Things Magical" and became generally known to the magical community.