This review is based on a read-through of the adventure. I've never played it, so my evaluation of how it's likely to play is colored by that lack of experience. Actual play may vary.
For more reviews, look at my Reviews page.
WGR6 The City of Skulls
by Carl Sargent
Published in 1993 by TSR
The City of Skulls is an adventure for 2e AD&D. This is a mission-based adventure. To make a long story short, the PCs are tasked by the King of Furyondy to go to Dorakaa, capital city of the lands of the demonic demi-god Iuz, and spring a valuable prisoner from jail.
The PCs get well equipped with potions, a few magical items the kingdom has spare, and scrolls of the spells they need to get close to Darokaa and back - specifically Plane Shift. They basically need to shift into Darokaa, close but not too close to the reality- and movement-warping gate that Iuz has to get back and forth to the Abyss.
The pressure is that, naturally, it's a one-shot raid. There isn't time or a safe place to rest, so the PCs have to stay alert with Potions of Vitality and conserve their HP and spell resources. Not only that, but there are the usual complications of a raid on a prison - prisoner location information is vague and passwords, locations, and details must be extracted from those in the know. Which is to say, only those high enough up to be trusted with that kind of information. So the PCs need to move constantly, conserve resources, deal efficiently with problems (which doesn't always mean lethally), and otherwise find a way to get by obstacles. Groups which methodically hammer through foes and take their time will find the task too big to complete.
The module itself is well put together and well written. It does open with a really long bit of boxed text - no multi-page nightmare like WG6 The Isle of the Ape, but still long. But the information that follows it is valuable - there is excellent guidance for the GM on how the principals will react to questions, what they know and what they'll share, what they have available for trade if the PCs want to swing some extra magic items out of their own extras, and so on. But otherwise it's just simple information on what is where, tactics and reactions special to the encounters. No boxed text, no fancy stuff, and enough details to run each and every room and scripted encounter area.
The adventure takes advantage of - and account well for - the problems with Team Chaotic Evil. That is, everyone is on their own team. Many NPCs will oppose the PCs for their own reasons, turncoat their nominal allies for personal reasons, and otherwise act in a disorganized fashion. They act well given their own powers and limitations, but the friction in a chaotic society is clear.
The need for stealth and the effects of a too-brutal too-obvious approach is handled with a mechanism called Notoriety. Any actions which draw attention to the PCs - fighting, being obvious enemies, killing major NPCs, causing wide-area damage or trashing the environment - increase their Notoriety score. The higher it gets, the more chance the PCs are noticed enough to draw patrols or a hit squad. The mechanism rewards stealth and cleverness nicely, and punishes brute force in a vicious circle. The PCs need to find the right measure of exterminating witnesses and letting those whose death will be felt too quickly escape. Hint: the really minor types will be too worried about their own skin, and the death of major types will be felt immediately even if they're killed secretly. Knowing who to fight, who to kill, who to let escape, and who to suborn, charm, or bribe is critical. At the same time the response is proportional to their actions and makes sense given the internecine violence of a CE society - the PCs aren't perceived as an existential threat right away, just as a problem to be solved by the underlings that can be spared for the task.
The adventure gives a lot of useful guidance for when the players get clever. Writeups of actions taken by actual groups in play-throughs (in playtest or tournaments, it's not clear) are given along with the results. It's very inspirational for the GM and helps drive home the idea that the GM needs to stay on his or her toes. Further, it has some great advice for GMs in general. For example, one powerful foe is only in the location occasionally. The adventure suggests that if the PCs have played well but luck has put them low on resources, then just skip the fight - the foe is elsewhere. If the PCs have played well but are still ready for a big fight, give one to them. I like that kind of advice because it's how I GM - I'm willing to let things slide if the PCs are having a hard time despite clever play, and I'm willing to give them an extra challenge if things went too easily and a good hard fight would make it all the more interesting.
The adventure itself is well-written. The maps are clearly drawn and easy to follow. The NPCs and monsters make sense in context and enough information to run them is present. Traps, treasures, and other details are well spelled out. Oh, and the traps are appropriately lethal. The only complaint is that some of the magical items and spells refer back to WGR5 Iuz the Evil. Some places give suggestions for replacements, others just assume you have that supplement. I'm not a big fan of supposedly self-contained material that needs stuff in other supplements not listed as required. Still, it's easy enough to just replace the material.
How would this be for GURPS?
In general, I think it would be good. The fights would be tough, but they're well-suited to both the brutally short fights that GURPS combat can result in and the tactical challenge of the set-piece fights and traps.
Standard GURPS mages would be much more able to access spells since recovery time is so quick, and those with Energy Reserve have dual-track recovery. Even so, this is a double-edged sword. The temptation to rest in a dangerous area for just a few minutes - or a lot of minutes - can spell disaster in Darokaa. At the same time, the more limited effects of GURPS spells would mean the PCs are less likely to go for broke on major spells.
The adventure is well written and interesting. It's long for a one-shot, but it's a high level adventure with lots of bits, so it doesn't feel too long. The challenge makes sense, the exposition fits, and overall the module conveys what you need to know to run it. If you're looking for a good D&D "prison break" module, this is a good deal.