Wall of ice

Wall of ice, formerly known as Veridon's ice wall, was an evocation spell that created a thick, opaque, sheet or dome of ice. After the Spellplague, only the wall form was available.

Wall of ice could be cast by sorcerers, wizards, and clerics who commanded the cold or ocean domains. In the time of Netheril, it could be cast by arcanists of the Inventive or Variation specializations.

Effects
All versions of this spell created a smooth, unbroken feature of ice, but they varied in size, shape, and support requirements. Older versions of this spell did not require the ice sheet to be anchored to anything, thus allowing a caster to cause it to fall upon opponents, creating an effect similar to ice storm. Another form that could be created before the Spellplague was a dome of at least 10 ft (3.1 m) radius. Walls and domes both required a solid anchor. Vertical walls were anchored to the floor, while slanted or horizontal walls required two anchoring surfaces. After the Spellplague, the wall was made up of contiguous 5 ft (1.5 m) square orthogonal segments anchored to the floor.

The thickness of the wall was originally determined by the level of the caster, being 1 in (2.5 cm) per level,   but after the Spellplague, the wall was a whopping 60 in (1.5 m) thick. The size of the wall was originally 10 ft2 (9.3 m2) per level in any dimensions up to the maximum area. Similarly, the radius of an ice dome could be increased by 1 ft (30 cm) for each level past the minimum necessary to cast wall of ice. Post Spellplague, the maximum length of the wall was 60 ft (18.3 m) and maximum height was 30 ft (9.1 m).

Ice formation required a clear area in which to form. The spell fizzled if cast in an area occupied by creatures or objects. The ice was frigidly cold, injuring those who tried to break through or even stand next to it. One version of this spell could be disrupted by an adjacent and particularly quick creature as it was being formed&mdash;if they succeeded, they took no damage and the wall dissipated. The ice was vulnerable to fire and especially strong magical fire. A fireball or fiery dragon breath could melt the earlier walls in about a minute, creating a large steamy fog cloud that filled the area for 10 minutes. The post-Spellplague wall melted in an hour unless it took sufficient damage from fire, in which case it was destroyed.

Components
In addition to verbal and somatic components, casting of wall of ice required a small fragment of quartz or rock crystal.

History
The spell was created by the arcanist Veridon of Netheril, ruler of the enclave of Lathery. He introduced it in 3369 NY (−490 DR) under the name Veridon's ice wall. It later became known simply as wall of ice.

Wall of ice was a common spell in Faerûn in the 1360s DR.