I just finished running this game with my players last night, and I will say we did have a blast. This is a fun dungeon crawl that took us approximately 12 hours to complete. It is relatively straight-forward in its setup, and provides a fun challenge for your murderhobos. That said, I do have a number of criticisms of the adventure-as-written.
- There are a fair number of inconsistencies in the adventure that would be fixed with proof reading. For instance whether Ahramon was a bard or a wizard, a sword in the tavern that is confusingly referenced but does not exist, or which spell Kholben has prepared via Contingency.
- A map is referenced early in chapter 2, but one is never provided. The castle is straightforward enough that it is easy to draw up a suitable map on your own, but the description of the ramparts and outer keep were unclear enough that it would have been helpful to visualize what the author intended.
- Several item names should be cross-checked with the DMG. Several item names in the adventure are incorrect, and it took us some time to identify the correct item (the Cloak of Spell Warding for example is actually the Mantle of Spell Resistance, and the Elven Boots are actually Boots of Elvenkind).
- It is unclear which edition this is written for, and there are some rule inconsistencies if you are running 5th edition D&D. Primarily this is found in the tactics listed for Kholben Ironfoot. In his first round, he is supposed to use Time Stop in order to cast several buffs on himself. Several of the recommended buffs are concentration spells, and as written Kholben has already cast Stone Skin (another concentration spell) on himself. Since only one spell can be concentrated on at a time, the DM must choose a new way to play out the encounter. It is also implied that Kholben uses his Signature Spell (Lightning Bolt) as though it were a cantrip, which is not how Signature Spell works in 5th edition. Finally, the potential final encounter (an undead red dragon) is more appropriate for a party of level 15 adventurers than a party of level 11 adventurers. The adventure does not provide a custom stat block for this monster, and instead recommends applying the Dracolich template to a Red Dragon (with no specification as to its age). The options in 5th edition are young, which would be woefully underpowered, or adult, which would have almost instantly TPK'd my party if I didn't hold back significantly in using its abilities.
Despite this criticisms, I do recommend the adventure if someone is looking for a nice dungeon crawl for their adventure. The criticisms listed above simply create additional work for the DM in what would otherwise be easy-to-run out-of-the-box adventure.