Although exploring Goth Gulgamel might be incentive enough for brave or foolhardy adventurers, there are other reasons to go here as well.
Recovery Mission
Sorn-Ulth orcs have ventured into the city and stolen some magical treasures. Divinations used to locate the stolen loot reveal that it lies within Goth Gulgamel, as do the thieves. No one knows that most of the sealing spells are gone from the fortress, so most assume that it would be impossible to get to the loot. Then again, the very fact that the divinations worked suggest that it might not be so impossible after all.
Find the Staff of the Magi
The player characters seek the staff of the magi. Their extensive research of historical texts and conversations with sages near and far have taught them that the artifact once numbered among Ghul’s treasures. However, it was lost in the Utterdark when Khelaeson (one of the Great Seven) helped dismantle much of Goth Gulgamel. In other words, the staff lies within a chamber that drifted off into the Utterdark, no longer connected to the rest of the fortress. Knowing this, a particularly wise sage recommends that a wish cast within the Utterdark itself might allow the PCs to brave that cold, dark void and locate the lost chamber of the staff. Of course, the lenses of the Utterdark would help, too. . . .
Getting to Dreta Phantas
The player characters need to get to the Dreaming City. Perhaps one or more of them have received dreams calling to them, dreams which make it clear to them that they must reach Dreta Phantas. Through these dreams, or through extensive research, they learn they can reach the stolen city through the Entropy Sphere—and that one can access the sphere only through Goth Gulgamel.
