*** SPOILER WARNING ****
A solid adventure with nice sword and sorcery flavor. The background story and the encounters make sense. I agree with what MadDog said, it's a bit heavy on the monsters, but after all this is Stygia.
On a side note, I dislike the whole "good vs evil" setup between the cults of Ibis and Set, but I guess that's Howard's fault. :shock: I would like to see the cult of Ibis portrayed with some ambiguity, instead of the do-gooders they always seem to be (the same can be said of the cult of Mitra, which probably has its zealous inquisitors and the like). The moral should be that all religions are corrupt to some degree.
Anyway, back to the adventure. The Kiss of Set ritual gives the recipient a lot of power points initially and as he levels up. This would be broken were it not for the fact that the ritual is meant as a plot device for NPCs (and this is clearly stated).
One question: Hsis'Arul and his mercenaries are headed from Stygia to Kaetta in Shem to stop the priests of Ibis. However, when the PCs go south from Kaetta and into Stygia across the bridge of Nebheth, Hsis'Arul and his men are suddenly behind the PCs (on the Shemite side of the river). Does this mean they crossed over to Shem somewhere else, went to Kaetta (and defeated the priest of Ibis?), and then go south towards Stygia again? Looking at the area map, it would make more sense if the Stygians actually came up from the south, and followed the tracks of the PCs to the ruins of Hepthnon, without ever going into Shem.
On the whole, a good and solid adventure.