The Yellow Sign (Hastur)

The Yellow Sign (Hastur): You know how to draw the mysterious Yellow Sign and can use it in your magic. Once per day when you cast a spell that involves magical writing, such as erase, exploding runes, glyph of warding, or any symbol, the save DC and caster level increases by one each.

OPEN GAME LICENSE Version 1.0a - All text is Open Game Content.