House defense glyph

House defense glyphs were one of the three types of drow runes used by drow, the other two being sacred glyphs and way-marker runes.

Description
Drow runes were always limned in black, be it with ink, paste, or inlay. The runes were elegant. They were made to look like flags or ornamentation around the symbol of a noble house.

Powers
A house defense glyph stored magic and unleashed it when triggered. The magic was triggered when someone who did not own the proper drow house insignia or did not say the password disturbed them. The powers of way-marker runes and the following powers were commonly stored into the house defense glyphs: a color spray effect, an enervation effect, a dispel magic effect; a magic reflection effect, an antimagic shell effect, a magic missile effect, a black fist effect that worked like a Bigby's clenched fist, or a blade barrier effect. They were not limited to these, and wizards and runecasters devised new ones.

History
By the 14 century DR, the technique to create sacred glyphs was already old.