Wall of thorns

Wall of thorns was a conjuration spell that called a dense, thorny thicket into existence.

Effects
A tangled mass of wiry scrub with needle-like thorns as long as a human finger was temporarily created by this spell. The size of the thicket was one 10 ft (3.1 m) cube per level of the caster and could be shaped in any contiguous path or structure up to the maximum volume the caster could summon. Optionally, the caster could make twice as many wall segments of only 5 ft (1.5 m) thickness. The barrier could be dismissed by the caster at any time.

Impacting or moving through these prickly shrubs subjected the unfortunate being to slashing damage from the thorns. Only creatures with the ability to move through overgrown terrain unhindered could pass wall of thorns at normal speed undamaged. The better the armor worn by the victim, the less harm was incurred. Sufficient armor coverage could result in no damage whatsoever. If a creature was caught in the area of effect as the matrix of thorns appeared, they were considered to have impacted the wall and took damage accordingly. If they remained motionless until the spell expired, no further harm occurred, but attempting to leave the area or cutting their way out was considered moving through the barrier and they would again be raked by thorns.

There were two versions of this spell. The older version required 40 minutes to hack or chop a path through a 10 ft (3.1 m) section safely. The newer version took 100 minutes to go the same distance. Because the newer wall was more dense, it took acts of strength to push through it, whereas the old wall did not impede motion if the victim was willing to brave the thorns.

The wall of thorns was immune to normal fire, but magical fire could set it ablaze and destroy it completely. The newer version burned away in 10 minutes while the older version became a wall of fire (with the cool side toward the caster) for 20 minutes before being consumed.

The barrier was not a living plant and therefore was not susceptible to spells that effect plants.

Components
This spell only needed verbal and somatic components to cast. However, in the oldest druidic tradition, all druid spells required mistletoe as their holy symbol, while the post-Second Sundering version of the spell required a handful of thorns as a material component.