Continuing where Waterdeep: Dragon Heist left off, Waterdeep: Dungeon of the Mad Mage takes the characters from levels 5-20 as they scour their way through 23 levels of Undermountain (although playing Dragon Heist first is entirely optional). Despite the number of levels covered, Dungeon of the Mad Mage is, unlike most of the D&D 5E supplements, not  labeled as a campaign. Rather, it is (accurately) labeled as an adventure, because the entire thing is one enormous super-dungeon (certainly the biggest dungeon for this edition of Dungeons & Dragons).

And Dungeon of the Mad Mage is dense in order to fit those 23 levels in. It clocks in at over 300 pages, beating out most of the rest of the recent Dungeons & Dragons books by over 50 pages. It has only seven pages of bestiary and no other appendices (such as a section of custom treasure), so almost all of that is the dungeon itself, with page count for things like monsters faced farmed out back to the Monster Manual. So expect to run into a lot of variations of the archmage. There’s also no ‘boxed’ text in the book – no big descriptions to read when the players enter a room, no speeches ready for NPCs to uncork. The information that’s needed to give those descriptions and make those speeches is there – it’s just not broken out, which would take up more space. From an editorial perspective, I picture the designers having these late-night sessions where they had to cut this, that, and the other in a desperate effort to make their page count target.

Most of the dungeon levels in Dungeon of the Mad Mage feature multiple factions, and there’s a little bit of connection between the levels. For example, one level might be controlled by hobgoblins, with Xanathar Guild incursions and a drow outpost, while the next level has the drow’s main base and a competing force of duergar (the drow House Auvryndar probably has the broadest coverage). Not all of these factions are evil … but it’s not too far off. It seems to be assumed that clearing the dungeon will take some time, as there are discussions of the ways in which the levels may change after/if they are ‘cleared’ by the PCs (and in what way they are dealt with, depending on the competing forces). This may require the PCs to go up and down manually, but a series of level-locked gates will allow some skipping of levels (I mean that level part literally; there is an NPC that controls access to the gates based on whether the PCs are high enough level; it is transparently an out-of-character functionality-driven mechanism).

While each level is mostly freestanding, there are thematic components between the levels. Everything here is controlled by Halaster Blackcloak, the eponymous mage who has been living in Undermountain since before Waterdeep was a city. The characters will see his spies, see statues of him, see simulacra of him, see construct versions of him, etc., etc. He also put many of the more noteworthy occupants of the dungeon in the dungeon, although for most of them this backstory will be invisible to the players.

However, other than “Halaster!” there isn’t a lot tying the dungeon together, and “crazy” is not much of a theme. The whole “mad mage” thing is really played up. Anytime there’s some random out-of-place thing that may or may not make much sense, it is chalked up to Halaster being crazy. But, to me, this ultimately makes the super-dungeon feel a bit random, instead of thematic. But then, I’m not really interested in naked statues of Halaster wearing a cowboy hat and riding a donkey. Maybe I’m alone in that preference.

But I think that’s intentional. The cohesion of Halaster is mostly just a false front for 23 different dungeons, which include (but are not limited to):

• Arcane Chambers: goblins, drow, and bandits fight over a level filled with leftover magical experiments;
• Twisted Caverns: drow watch and wait as an aboleth wrecks the ‘native’ kuo-toa, who may get the PCs involved in the construction of their new ‘god;’
• Wyllowwood: the friendliest level in the dungeon, this is a place to remember that encounters can sometimes be overcome without combat;
• Maddgoth’s Castle: a re-imagination of 1996’s Undermountain: Maddgoth’s Castle, this level features a tiny castle that the characters will need to shrink down to access;
• Dweomercore: Halaster’s School of Witchcraft and Wizardry is full of characters who are by degrees insane and evil; but that doesn’t mean there isn’t politics to do;
• Trobriand’s Graveyard: hordes of constructs (and possibly a machine to make more) occupy this level that was originally a scrap heap for one of Halaster’s apprentices, and is currently occupied by an adventurer who decided it would be more fun to hang around after his buddies died;
• Obstacle Course: in addition to the number of traps one might expect with a name like ‘obstacle course,’ this level features a death tyrant and the first appearance of the gith;
• Crystal Labyrinth: this ‘level’ includes the ability to teleport (a mode of transportation that is generally unavailable in Undermountain) to the hollowed-out core of one of the asteroids orbiting Toril (the planet on which the Forgotten Realms is set), where most of the gith reside, along with their red dragon mounts;
• Vanrakdoom (by the way, that’s “domain of Vanrak,” not “doom of Vanrak”): provides one of the few places where there is a spark of good amidst the evil, as one of the two main ‘bosses’ on this level (a shadow dragon) can be restored to his original condition, if the characters can figure out his history with the already-redeemed Vanrak;
• Caverns of Ooze: despite the title, this level is most memorable for the spelljamming ship that got stuck in it, to include a mind flayer pirate captain (but don’t worry, there are plenty of oozes as well);
• Shadowdusk Hold: the last stop before Halaster’s level, the players might think that redemption will come up here again (as it did in the level immediately before, and as it did in the Vanrakadoom), but they will have no such luck facing the death knights and evil dragon here;
• Mad Wizard’s Lair: the ultimate destination, this single level is paced to have a couple of level increases while on the same level, as the characters battle the Mad Mage’s most powerful apprentices and then, one presumes, Halaster himself.

Note that, with so many levels, it may be helpful to pick up the “Maps and Miscellany” pack, which has maps for all 23 levels, plus randomizer cards used for elder runes and secrets of the dungeon. But note that, with so many maps, these are smaller maps for DM reference, not big ones you can throw out on the table (which you might not want to do anyway, since there is definitely a big exploration element here).

I think that what players think of Dungeon of the Mad Mage will turn on what they think of the unspoken concept of a big, random super-dungeon. If that’s of interest, then Dungeon of the Mad Made fulfills the concept very well. But some players will wish for more plot or cohesion.

Promotional consideration was provided in the form of a review copy.