"The Wand of Orcus is an incredibly powerful artifact when fully assembled, but the component parts have little power by themselves. Four of the demon lords (Orcus himself, Demogorgon, Graz'zt & Obox-Ob) each seek to acquire the complete Wand, which would surely cement their claim to be Prince of Demons. Not only would this turn the tide of the Blood War in their favor, but with the full power of the Abyss at their command, they would be able to strike at the Upper Planes."
You can kill Obox (Zio), Grazzt (Azz) and Demo (Maw) with Infestation of Maggots Druid spell. Have your cleric serendipity, prayer, tide. Druid mass spam maggots and win. If Druid is lower, GR him. Will drop them quick and painless.