Summon Demon

Type of Feat: Class
Prerequisite: Thrall of Graz'zt
At 4th level, a Thrall of Graz'zt can summon a demon of 5 HD or less once per day. This spell functions as a summon monster spell.

The HD of the demon summoned increases to 10 HD at level 9, 15 HD at level 15, 20 HD at level 20, 25 HD at level 25, and 30 HD at level 30.