We've mixed up the gods a bit for this campaign, Rhialto. We're using a fairly generic game world based on the locales in the WotC Adventure Path modules, rather than Greyhawk proper. I've used many of the Greyhawk deities presented in the Player's Handbook, but Nerull has given way to Sheol, a LN death god. Sheol was created by the PC who plays Tothla, with some input from me. Sheol's priests use a modified death domain, and have the granted power to detect undead at will. Readers will learn more about Sheol here as the story unfolds.