Wall of bones

Wall of bones was a spell used by necromancers and wu jen. The spell was very rare outside Kara-Tur.

Effects
When cast, a wall of bones erupted from the ground. The shape was determined by the caster. The wall was composed of a random assortment of bones from various creatures. The wall could be horizontal or vertical and required a solid foundation to remain standing. As the wall had many spaces between the bones, it did not provide complete cover and a small creature could crawl through it, although this was painful to the creature was they were scraped by the sharp edges of broken bones.A strong enough creature could break through the wall. IF the spell was cast in an area occupied by creatures, the wall formed around the creatures, which remained embedded in the wall unless strong enough to break free. The spell was unaffected by animate dead and could not be cast in the phlogiston.

Components
In addition to verbal and somatic components, the spell required a material component, a branch from a dead tree that grew in a graveyard.