No. 5: Durlag’s Tower (BG1: TotSC)
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On the flip side, the dungeon is again a bit too large and there are a couple annoying puzzles, although the bad puzzles are mercifully not as irritating as those in Watcher's Keep. Specifically, I mean the puzzles accessed from the 4th floor where the player has to answer historical questions posed by the statues. (Remember the one where the correct answer was something like, "we came from the west, then the north, then the east, then again from the east, and finally from the west again." – Ugh!) As a point of fact, the entire 3rd floor could be lopped out of the dungeon along with the horrid chess board where only you have to play by the rules. But even still, that level isn't quite the loss of the 3rd level of Watcher's Keep. Finally, the boss is a bit of a let-down because, although the demonknight is hinted at a few times, he doesn't really come to the fore until very near the end. To the contrary, you can complete 80% of the dungeon all the while thinking it fell simply to an external attack on Durlag's clan before finally learning that the doppelgangers were merely a manifestation of "the evil that was already there." Nevertheless, a better story and fewer irritants land Durlag's Tower above its BGII sibling.
No. 4: The Ruined Moathouse (ToEE)
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I only have three slight criticisms. First, there wasn't quite enough empty space; indeed, some of the monsters were right on top of each other. Second, there were no true non-combat encounters. Finally, the end boss, a cleric named Lareth the Beautiful, while having an interesting moniker for an evil henchman, is just a more powerful adventurer with no apparent motivation other than being a bastard in service to the Temple of Elemental Evil. Nevertheless, this dungeon is nearly 100% pure fun.
No. 3: Soloria (NWN2 Module: Trinity)
Soloria is damned near perfect as a dungeon in every way. Its backstory as an old school of magic in the fabled elven city of Myth Drannor means it's chock-full of lost tales, not to mention powerful loot and old forgotten magics. The atmosphere is utterly amazing with every detail really bringing to life this relic of a bygone age. But while the dead certainly rule here, they are not alone. The party must face hags, giant spiders, rival adventurers, and even a well-placed doombat in addition to the shambling corpses and ghosts of long-dead students. And a Death Tyrant, while technically dead, poses a completely different kind of challenge as well. But combat is only a small number of the obstacles the party will face in Soloria. Collapsed bridges no longer span wide chasms that nevertheless must be crossed, barriers of ancient magics must somehow be dispelled, and magical mouths demand answers to questions long since forgotten. There are traps galore, though none stand out as being particularly unfair, and there are so many secret doors and compartments within that I am certain I have still not seen all that Soloria has to offer. Finally, the dungeon's boss, the ancient lich Azimer, is memorable not only as a powerful adversary, but as a character. Hints of a lost love and regrets from his time as headmaster of the academy appear to have driven Azimer mad, causing him to fondly chide the party's wayward ways one moment (i.e. believing them to be students at a still-functioning academy) and then trying to kill them the next.
If Soloria had any negatives as a dungeon, they would be slight indeed. First, it's too small. This would be a petty complaint if I was judging this module strictly as an amateur work, but since I'm placing it on a list of all-time best dungeons, it gets the same treatment as everything else. Second, it does have a little bit of a confusing layout, and one wonders how it could have successfully operated as an academy back in the day. Finally, related to point two, it's a bit of a frankendungeon. I gather parts of the academy have caved in, so the dungeon regularly switches from stonework to earthen tunnels and back, sometimes seemingly at random. But these are only meant to be the slimmest of criticisms for a mostly awe-inspiring dungeon.
No. 2: The Windspear Hills (BG2)
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So why isn't the Windspear Hills at #1? Honestly, I'd have no qualms pushing it all the way up the list, but in the end I placed another entry a hair above this one. The Windpear Hills has a couple minor problems. First, it's basically one level with only Firkraag's lair and a small cave with a couple encounters outside that level. Second, there isn't a solid non-combat encounter. Third, the subplot with Samia and King Strohm's tomb is interesting, but misplaced, and it ruins the dungeon's narrative. Is this dungeon a tomb or a dragon's lair? If you think I'm being nitpicky here - maybe you think the dragon moved into a tomb and expanded it for his own purposes - then answer why greedy ol' Firkraag wouldn't seize the existing treasure for himself, especially since the sword and shield are designed to slay dragons. Perhaps it was the guardians that scared him off... oh, wait. They're fire-based guardians and Firkraag is a red dragon. Oops! See? No consistency, and we have to try real hard to concoct a story ourselves to make it fit. And then how did Samia get in past Firkraag's henchmen? Shouldn't we find either her corpse or the hobgoblins' corpses in the front room? But this negative doesn't ding the Windspear Hills as much as the 3rd level of Watcher's Keep, for example, because while it was inconsistent with the dungeon, it wasn't boring and frustrating as an objective. Inherently, collecting mask fragments so you can see an otherwise-invisible guardian is kind of cool. So these really are minor quibbles with an overall masterpiece.
No. 1: The de'Arnise Keep (BG2)
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Yes, the choice will no doubt cause controversy, but this dungeon pretty much hits every point needed to be truly great. It is the perfect size and well laid out. The back-story is well-defined, and the ruined castle is quite atmospheric. It has a nice mix of encounters, plenty of creepy places to investigate, and just the right number of secret doors and traps to keep things interesting. Finding and reassembling the Flail of Ages, rescuing Daleson, the Lady Delcia, and Glaicas (if you break the domination spell on him), and opening the drawbridge all provide non-combat objectives. The golem-guarded treasure room on the second floor allows for a neat diversion entirely separate from the main quest while remaining consistent within the dungeon's narrative, and there are five different types of monsters (troll, yuan-ti, umberhulks, golems, and an otyugh), thereby ensuring a fair number of different encounters types. Finally, the monsters are well spaced-out, meaning it is easy to envision (i.e. role-play) a small crack party being able to enter the keep and wiping out its inhabitants a few at a time without having to suspend belief too much.
If I had to say anything bad about this dungeon, I would have to say that its boss, a big troll named Torgal, is on the weak side as a character, although his hints of a larger alliance against the de'Arnise family are intriguing shadows of something more. (Later we learn he was probably in league with the Roenalls, but that's outside the dungeon experience.) All-in-all, Nalia may be annoying to deal with, but her family's keep most definitely is not.
So when deciding on #1, I had to choose between a dungeon that did everything right except for have a slightly weak boss or a dungeon that had a couple minor flaws but a kick-ass boss. In the end, I chose to reward the one that was better over the first three hours over the one that was better for the last ten minutes.
I'm going to have one more post in this series in which I discuss some of the other major dungeons in the various franchises and why they did not make the list. Stay tuned!