A One-Round Continuous Living Greyhawk Sheldomar Valley Meta-Regional Adventure
From the introduction:
This must be the place. Now the question: is the time right to recover the lost legacy of the Suel? That depends on whom you ask. It is highly recommended that the party contain at least one wizard.
A Sheldomar Valley metaregional adventure for [character levels] 8 - 16.
Part 2 of the Mysteries of the Suss series.