Drow rune

A drow rune was a defensive form of rune magic used by the drow.

Description
Drow runes were elegant. They limned them with black material, often ink, paste, or inlay.

Powers
Two versions of magical symbols existed. First, there were the ones enchanted with glyph of warding. Second, there were the ones specifically created by drow runecasters for specific locations with special spells developed only for this purpose.

Their magic was activated by one of three methods: by touching the rune, by movement of the surface they were placed upon&mdash;like opening a rune-rigged door&mdash;or by passing through a place that was connected to a rune. If they were made invisible, they visibly flashed on activation. Unlike a glyph of warding or greater glyph of warding, a drow rune's powers were not expended on activation. However, there was a one-minute interval between successive activations.

They were hard to bypass. Both magical means like casting dispel magic or remove traps or mundane means of which rogues were capable had only a one in six chance of success. One in three times, they turned the rune inert for one to two minutes, and half the time, the meddling caused it to trigger even during the one-minute interval. Sure ways to safely bypass these runes were to cast antimagic shell, being a priestess of Lolth, or having a drow house insignia. However, these were merely general rules.

There were a total three types of drow runes. The way-marker runes, used in places the drow patrolled but did not inhabit; the sacred glyphs, used in places sacred to Lolth; and the house defense glyphs, used to defend houses.

Magical runes of the drow used a special ink that was magical. The formulae of it was a secret known to the noble houses. The most powerful of these secret ink was one called everdark that made the magical effects stronger.

History
Drow in general had an aptitude for glyphs and runes and by the 14 century DR, their history of using rune magic to protect specific locations was very old.

Notable Owners
Only the richest and most powerful among the drow could afford to use drow runes.