Hey, Stat Rollers! Bill with Roll Stats here, and today, I’m diving into one of the most iconic tournament modules ever published for Dungeons & Dragons. That’s right, I’m talking about number thirty on the Dungeon Magazine “Top 30 D&D Adventures of All Time,” the warped, reality-bending corridors of Dungeon Module C2: The Ghost Tower of Inverness!

Written by Allen Hammack and used initially as a tournament adventure for Wintercon VIII in 1979 before getting the complete TSR treatment in 1980, The Ghost Tower of Inverness is a classic example of what early AD&D tournament play was all about: deadly traps, high-stakes puzzles, wild, magical effects, and exactly zero room for error.

But does it still hold up in 2025? Can it hang with today’s narrative-driven adventures and OSR systems? Is this soul-devouring Gem still worth seeking out?

Let’s dive in and find out!

But before we go any further, this is your spoiler warning—I’m discussing the details of Dungeon Module C2: The Ghost Tower of Inverness in this video. So, if you want to experience it firsthand, maybe send your DM this way instead and come back after your first playthrough.

The History and Legacy of C2: The Ghost Tower of Inverness

The Ghost Tower of Inverness holds a special place in my heart and in D&D history. It was TSR’s second official tournament module after the infamous Hidden Shrine of Tamoachan. And, like its predecessor, C2 was built to challenge your players with limited time and space, offering fast-paced exploration, brutal traps, and room-by-room scoring. Tournament players had four hours to make it through the whole thing or die trying.

Originally run with pre-gens and a scoring system, the module includes all the classic hallmarks of a convention adventure: tight pacing, high difficulty, and minimal downtime. It’s a brilliant example of creating intensity without needing an epic storyline. That being said, the lore behind the tower is still pretty cool.

The ruined Castle Inverness looms over the Abbor-Alz hills in the World of Greyhawk setting. Your players are sent to retrieve the Soul Gem, a powerful artifact created by the mad wizard Galap-Dreidel which is locked away inside the Ghost Tower—a mystical structure that phases in and out of reality and time.

The Setup: C2: The Ghost Tower of Inverness

The module opens with a bit of mythic worldbuilding for Greyhawk. It throws you back to the days before the Invoked Devastation and the Rain of Colorless Fire. Before that magical apocalypse, the Abbor-Alz mountains were sharper, the Flan were still newcomers, and nestled between the Bright Desert and the Selintan River stood a fortress so mighty it was said to resist all natural and magical threats: Inverness!

But, of course, this isn’t your run-of-the-mill keep. This was home to Galap-Dreidel, a wizard of terrifying power and vision. I mean, this guy didn’t just build a tower—he raised it from the living rock and then yanked it out of time itself so the traps and monsters inside would never age, decay, or even need food. Convenient? Sure, but cool as hell? Most definitely!

The crown jewel—literally and figuratively—was the Soul Gem. A meteorite turned soul-sucking diamond that Galap-Dreidel shaped with forbidden magic. It could trap the souls of the living and bend them to his will. And the thing is, he didn’t just wield it—he taught it to defend itself!

I mean, that’s such a chilling concept! I’ll be honest, I’ve stolen that for homebrew campaigns more than once!

Eventually, the wizard disappears on a mysterious journey.

No death scene.

No battle.

Just gone.

Naturally, the terrified locals decide it’s time to storm the castle. They destroy the tower—or think they do. But the legends say it still appears on misty nights, flickering in and out of reality.

For real though. That’s some serious gothic fantasy right there. If that doesn’t make your players lean in, I don’t know what will.

Enter the Seer of Urnst (and your Players)

The Soul Gem legend persisted for centuries, but it’s the Seer of Urnst who finally pieces together the means to control it. He investigates the ruins of the keep but gets turned back. So he appeals to the Duke, Justinian Lorinar, with a pitch that only a wizard could make: “Let’s go recover a cursed soul-trapping gem for… ya know… protection.”

Naturally, the Seer knows he can’t do it alone, so he recommends a party of adventurers be strongly encouraged to try. In true AD&D fashion, that railroad… I mean “encouragement” might be a geas, or the Duke might just handpick some criminals with the promise of clemency.

So right now you’re saying, “Bill, another railroad?” and yeah, I’m not going to lie. Your players start in chains—literally. Each one is a prisoner or debt-servant, faced with a choice. Retrieve the Gem or return to prison. So yeah… It’s a railroad. But, it sets up a perfect framework for your players to be thrown into danger, treasure, and glory with a sharp deadline and no guarantee of survival.

I mean they’re dragged before Duke Justinian, who reads off their crimes like a judge handing down sentences. Then the Duke drops the hook: recover the Soul Gem from the ruins of Keep Inverness, and earn your freedom. The Seer even sweetens the deal with a magical recall amulet—press the button, and you teleport back to the palace. Fail to retrieve the Gem, though, and it’s back to the dungeon.

It’s kind of like John Carpenter’s “Escape from New York” except it’s in Greyhawk, and your players are Snake Plisskin, Brain, Maggie, and Cabbie.

Prepping to run C2: The Ghost Tower of Inverness

Look, if you’re going to run this thing you’ve gotta do your homework. This isn’t the kind of module you can skim the night before and hope to wing it. It’s packed with unique mechanics, custom puzzles, and layered encounters. So you’re going to want to read it cover to cover, make margin notes, and maybe even sketch out some of the trickier areas.

The inclusion of visual aids helps. TSR understood that a striking illustration could bring a strange room or a puzzle to life. So, if you’re running this, I recommend printing out those aids or recreating them digitally if you’re playing online.

And here’s a big one—this module punishes careless magic use. Fireball or lightning bolt in the dungeon? Boom. Instant collapse, with extra damage, and your players will need to dig themselves out. It’s a mechanic that drives home the fragility of the ruins and discourages blasting your way through everything.

And another note of caution: experienced characters are not a substitute for experienced players. This isn’t the kind of module that forgives rookie mistakes. The module suggests 5–10 characters, of levels 5–7, with a good mix of thief, cleric, and magic-user, so you’re going to want to buff the party with an NPC or two, but the key is running this module for the right table. This isn’t a module for noobs, this module works best with experienced players.

This dungeon rewards careful thought, teamwork, and old-school caution. If your group is more used to modern, narrative-driven adventures, they may get frustrated fast. But if they lean in, Ghost Tower will reward them with one of the most memorable adventures you can run.

Bottom line? If your group loves atmosphere, tactical challenge, and letting the dungeon itself be the star, you’re going to love C2! If you haven’t run The Ghost Tower of Inverness yet, you’re missing out on one of the true gems—no pun intended—of early D&D design.

Welcome to the Upper Ruins of The Ghost Tower of Inverness

Room 1: The Gateway – Immediately, The Ghost Tower of Inverness sets the tone with a strong visual design. The keep looms above the fog, the towers stabbing into storm clouds like crooked fingers of stone. The portcullis is there as a temptation—but a bad one.

The clever party will notice safer entry points: the holes in the walls. This is a classic example of early D&D encouraging exploration and lateral thinking over brute force.

As a DM, I love how this entry scene says, “You’re not here to break walls—you’re here to outthink them.”

Room 2: Rubble – Now here’s one of those traps that teaches players the old-school mindset. In the middle of the courtyard is a giant mound of ancient rubble, the remains of what was once the central tower. But hidden in the map’s shaded areas are four unstable sections—pitfalls ready to drop a character 20 feet for 2d6 damage.

It teaches players to poke, prod, test, and not just charge blindly ahead. It’s one of those subtle rewards for careful play that exemplifies old-school design.

Room 3: Tower Doors – Each of the four corner towers offers an entry into the dungeon via a spiral staircase. The upper levels are collapsed and sealed off—so if your players get clever and try to teleport up there, they’re probably dead.

The doors themselves are rusted and stuck. Your party can pick or force them, but inside they’ll find the same thing: a spiral staircase that leads down about 30 feet before it goes pitch black. At that point, torches or light spells become necessary. They’re descending into the unknown—and you should play that up with eerie descriptions and faint, echoing sounds from below.

The Dungeon Level and the Four KEYS

The meat of the dungeon crawl begins here. And I’ve gotta say, this is some of the smartest, most modular dungeon designs from this era.

The entire level is built around four different paths—each leading to a segment of a four-part puzzle item called the KEY. Each path contains its own environmental challenges, puzzles, or nasty monsters, and the party has to explore all four areas to get into the central room.

The KEYS themselves are pretty cool—blue-gray metal bars with a circular end. When you combine them properly, they lock into an “L” shape. Combine all four and you get a perfect 8″ square shape that matches the indentation on the central room’s doors. It’s elegant, it’s visual, and it ties in thematically with the castle’s layout. Galap-Dreidel built his fortress with symmetry in mind, and it’s reflected in how the puzzle pieces come together.

From a gameplay perspective, this is a fantastic design. It lets your players explore in the order they choose. I mean, it has a clear end goal, and it rewards communication and planning. Every time I’ve run this, the party slowly pieces together what’s happening—and when someone says, “I think we need all four parts of this key,” I can’t help but grin and nod.

Room 4: Staircase Landing – Each tower drops you into one of these. There’s nothing mechanically significant about them, but it’s a great transition space where you can describe the shift from ruined stone to worked dungeon walls. I usually toss in cobwebs, the smell of stale air, and the feeling of a place sealed away from the world.

Southeast Quadrant of C2: The Ghost Tower of Inverness

Room 5: Monster Squares – This room’s a random encounter gauntlet. Step on a numbered square, and a monster appears out of thin air. It’s a classic old-school D&D trick—nothing obvious, but danger in the floor itself. And I really like how each monster is unique and only appears once, and your party never knows what they’ll get. It creates real tension every time someone steps forward.

Room 6: The Bugbear Room – Okay, I mean, this room has sixteen bugbears in temporal stasis and a sarcophagus in the back! Each time one of your players passes through a doorway, four of the bugbears animate.

This is one of those encounters that screams old-school design. You can have some great moments of confusion and panic as your players realize the triggers. And there’s a KEY hidden inside the sarcophagus—but it takes some brawn (a combined strength of 35) to open.

I like to play up the suspense here—silent monsters, that uncanny stillness, the sense that something’s wrong. Once your players realize movement activates the bugbears, you can practically hear the gears turning in their heads.

Southwest Quadrant of C2: The Ghost Tower of Inverness

Room 7: Manticore Lair – Behind the rubble piles in this collapsed chamber lives a manticore. If one of your players gets too close, it springs to the top and starts launching spikes. And this one’s brutal if your players aren’t cautious—and it really highlights the need for scouting and ranged options.

There is really no way to avoid this encounter either, because there’s a KEY buried in the skeleton-filled lair, along with a magic set of chainmail, a scroll, and two potions. And the potions even come with clever “sip clues” to hint at their effects. It’s little details like that I love—it encourages experimentation, not just rote spell use.

Room 8: Illusory Rolling Boulder – This one is a total head trip. Open the door, and a giant stone boulder comes roaring toward you—but it’s just an illusion. If it “hits” one of your players, they vanish, and only when they touch another player does the illusion break.

It’s one of those gotchas that can cause chaos but ya know, in a fun way. I mean, I’ve had entire parties think half their group was dead and panic-sprint back into Room 7 before realizing what happened.

Northwest Quadrant of C2: The Ghost Tower of Inverness

Room 9: The Crystal Pedestal – Okay, Now we’re really getting cerebral. A massive crystal ball on a pedestal contains strange shapes inside. Four engraved words release four monsters—an ape, a toad, a minotaur, and an owlbear. And the only way to get through is to say the right words and fight the monsters one by one.

If your party says the wrong combinations or rushes it, multiple monsters spawn at once. And, I mean there’s no physical or magical way to bypass the challenge—but trust me, your players are going to try. But, they’ve got to engage with the puzzle, there is no other way. I love watching players debate whether to say the words or try to “game” the system.

Room 10: The Tunnel Room – This room is home to a treasure chest—and a lurking umber hulk that ambushes your players if they stop to investigate. It’s a classic old-school trap of greed. Trust me… Confusion from the Umber Hulk’s gaze can turn a fight into a total mess.

Northeast Quadrant of C2: The Ghost Tower of Inverness

Room 11: The Bead Curtain – So your party sees a curtain of magical beads that blocks sight, sound, and movement unless forced or dispelled. If they force their way through, they risk falling, getting surprised, and fighting gnolls (or worse) on the other side.

And here’s the thing! The more times they go through, the tougher the encounters get! It’s a fun encounter that rewards planning—and punishes indecision.

Room 12–13: The Cubicles and Chess Room – Okay, so this is everyone’s favorite part of the entire dungeon, and definitely the one that everyone remembers!

When your party steps into one of five carved cubicles, they’re sealed in, transported along a hidden track, and ejected into a 40×40 chessboard room where the floor punishes incorrect movements based on chess rules! Each player must move like a specific chess piece—rook, bishop, knight, etc.—and moving wrong costs hit points.

It’s genius. It turns movement into a literal puzzle. And they MUST solve it because when they grasp the statue in the far corner they’ll find another one of the KEYS.

Honestly… This room alone is worth running the module!

Room 14: The Metal Doors – Okay, so here’s the gate to the central chamber—a smooth metal wall with an indentation shaped exactly like the four-part KEY. This is the payoff to all that exploration your party has done. Only the assembled KEY can open the way, and magic is completely nullified here.

No shortcuts.

No tricks.

This is why I said earlier that experienced characters are not a substitute for experienced players. This isn’t the kind of module that forgives rookie mistakes. They solve this puzzle, or they fail.

Room 15: The Central Room – Is a smooth, featureless room with eight padded reclining chairs. The moment your party steps inside, the doors slam shut, and the room activates. Anyone standing gets knocked down and takes damage unless they were smart enough to sit.

This is the moment the Ghost Tower “activates.” A hole opens in the ceiling., and your party is about to be launched—literally—into the true heart of the tower. And that’s where things really get weird.

In short? This whole section is a beautifully constructed dungeon crawl that rewards curiosity, teamwork, caution, and cleverness. Whether you’re running it straight from the module or adapting it for campaign play, it’s one of TSR’s strongest examples of what makes classic D&D such a blast to run.

The dungeon levels of the Ghost Tower of Inverness is a puzzle box in the truest sense. One that delights in misdirecting, surprising, and challenging your players at every turn.

But they’ve only just begun…

Reality-Bending Madness in C2: The Ghost Tower of Inverness

Now we’re at the crown jewel—pun entirely intended—of C2: The Ghost Tower of Inverness. This is where things truly go from “cool classic dungeon crawl” to “weird planar mind-bending time-traveling soul-sucking high-concept epic.” Strap in, because this is TSR at its wildest and most creative.

Welcome to the Ghost Tower proper my friends!

Because here’s the twist—and it’s one I absolutely love: Room 15 isn’t just a room. It’s a time portal.

That’s right. The minute your party steps into the center chamber, they’re transported back to the time before the ruins—when the Ghost Tower of Inverness still stood tall and proud. Of course your players won’t know this, so it creates this amazing tonal shift. Suddenly they’re not just exploring a ruined dungeon—they’re trapped inside a magically preserved slice of the past, filled with timeless elemental guardians, traps, and the infamous Soul Gem.

And in true old-school fashion, magic’s got limitations here. No teleporting out. No pass wall or dimension door to shortcut through. Even your best spells are stymied by the ancient anti-magic shield wrapped around the tower like a big arcane bubble. The only way out? The Amulet of Recall that was given to them by the Seer. That’s their magical lifeline home.

Do you want tension? That’s tension. You’re cut off from the present, moving through an alien place out of time, and the only way out is through.

Ascending the Tower – One Elemental Level at a Time

Room 16: The Chute – Their vertical gateway. After all that dungeon crawling, your players now have to climb up a shaft to ascend into the actual tower. It’s narrow, and 70 feet tall in total, with bronze rungs in the upper section. It’s got that dungeon-to-tower transition feel like your players are climbing out of the world they know and into something stranger.

Room 17-19: The Air Level – Thick mist. Low visibility. Loose, treacherous footing. It’s the kind of encounter I love because it’s less about monsters and more about the environment messing with your party. Are your players sprinting or charging? There’s a chance they’ll slip and lose time and initiative or even get caught flat-footed.

And trust me, they don’t want to do that!

Enter the Hieracosphinx—a big, nasty, flying lion-eagle hybrid that dives out of the fog like a jet. It charges first, gets a bonus to hit, then drops into melee. If your party survives, they’ll find a ton of treasure—but first!

Three pteranodons swoop down from the mists on the spiral stairs. I mean, surprise is likely, and they don’t fight fair. They’re definitely going to try to knock someone off the steps for a very nasty fall. I always picture this encounter like a pulp serial moment—heroes clinging to an iron spiral stair while winged horrors scream out of the fog.

Room 20: The Earth Level – From mist to jungle. Your players emerge into a humid, dense thicket—trees towering up to the ceiling, undergrowth choking their path. They can’t just wander here. They either stick to the trail or cast nature-based spells to manipulate the flora.

And of course, hiding in the canopy are su-monsters—creepy psychic apes from back in the day. Here, they’re de-psionicked (thankfully), but they still drop down for sudden, brutal attacks. But, if your players fight smart, they can limit how many su-monsters arrive.

Room 22: The Medusa’s Garden – So, this one’s a classic gotcha, but it’s fair. The medusa is disguised as a serene monk tending roses in a clearing. She’s even singing—a beautiful, haunting melody. If your players approach hastily or call out to her, she turns, and bam: save vs. petrification, or you’re a statue, my friend!

And this is another example of why experienced characters are not a substitute for experienced players: smart players avert their eyes, or use clever solutions like mirrors, blindfolds, or indirect strikes. Players who get hasty get stoned.

Admittedly, the treasure in the garden is phenomenal and definitely worth it. Your players will recover a false-bottom chest with bracers of defense, a diamond worth 10,000 gp, and enough gems to make a dragon blush. But they need to be careful—those rose thorns can put them into a magical sleep if they don’t watch their hands.

Room 24: The Fire Level – Okay, this one… This one is a straight-up Death Metal Album Cover moment! Your party emerges onto a stone platform over a literal sea of fire! Narrow paths cross the flames. Breathing is tough. Everything’s sizzling. And across the way, in front of the exit, is a fire giant ready to play hot-potato with boulders!

Did I mention there’s also a reverse gravity field?

Yup. The map (Visual Aid #3) helps you adjudicate this. Any player stepping into the hidden field gets launched upward. If they catch the lip of the shaft, they can climb to the next level. If not? Sploosh into the ceiling, then back down into the fire unless they’ve got magic like feather fall. It’s a test of both clever thinking and raw luck.

Plus! In non-tournament play, 12 flaming, blood-sucking bats erupt from the flames and latch onto your players, draining HP over several rounds. They’re terrifying little bastards—immune to fire, can see invisible foes, and they burn when they die. I love using these to up the chaos!

Behind the fire giant? A ring of feather falling (helpful for what’s to come), a treasure-filled sarcophagus, a gorgeous platinum crown worth a king’s ransom, and a staircase. But be careful—it’s a fake staircase. The real way up is falling into the reverse gravity field and going through the hidden hole in the ceiling.

Room 28: The Water Level – Ah, the old bait-and-sink. Any player who fails to grab the ceiling lip from the gravity field ends up here: crashing into 15 feet of water. It’s warm and salty, with coral reefs, a tiny island, and one big, nasty prehistoric fish lurking around.

Trust me when I tell you, this level is one of the most deadly for unprepared parties.

Your players must quickly remove their armor to keep from drowning. And the rules here are detailed and brutal! If you’re wearing heavy gear? It’s a race against the clock—and death by exhaustion.

The coral provides some cover, but if your players venture too far they trigger attacks by demonic manta rays. And they’re cunning, they’re fast, and their leader has cleric spells and a ring of protection +3!

And did I mention the hatchway? That’s their exit—but opening it attracts the manta rays like blood in the water. If your players are able to open it, they swim “up” through a flooded tunnel, and boom—gravity reverts and they surface in…

Room 33: The Jewel Room – This is it. The big one. The culmination of the whole module! The Soul Gem floats in the middle of a massive domed room that is divided into eight sectors. It’s a white, melon-sized diamond, slowly rotating, and pulsing with magical power, and at the end of every round, it randomly blasts one of the eight sectors (and any player in that sector) with a soul-stealing white ray!

The first shot, well it never hits the entry zone, but after that, it’s pure chaos!

If a character fails their save vs petrification, their soul is ripped from their body, dragged into the Gem, and they’re dead, just dead. Their body is still there, but it’s a bleached-white husk, and all their magic items are drained (except the Recall Amulet if they have it).

If they want to grab the Gem? First, they have to shatter the invisible force sphere around it, which is, of course, immune to spells and can only be struck with melee attacks.

Oh, and each point of damage a player does? They take it too. Because of course they do!

Destroy the Gem with a natural 20? Sure. But then the millions of trapped souls are unleashed and they go berserk, slaughtering everything unless someone hits the Recall Amulet fast. It’s high-stakes pressure with a terrifying visual payoff.

Once the Gem is secured and the Recall Amulet is pressed, everyone touching the person holding it (including dead bodies!) teleports back to the Seer’s lab. And as a bone to your players the Seer, being a master of the Gem, can restore souls to their original bodies—or to new ones, if needed. It’s a poetic way to wrap up what is essentially a cosmic heist.

Honestly, the Ghost Tower isn’t just a tournament module—it’s a great adventure for campaign-play too. Each elemental level is tight, thematic, and packed with unique dangers. There’s no filler, and everything builds toward the climax.

I’ve run this module multiple times, and every time, players remember it. The invisible forcefield. The time travel. The chess room. The fire level’s hidden gravity. The terror of the Soul Gem’s ray. These are iconic D&D moments.

It’s not a module for the faint of heart. It’s punishing. It’s clever. And most of all it’s lethal.

But, it’s also absolutely brilliant!

If you’re looking to give your players a night they’ll talk about for years, C2: The Ghost Tower of Inverness is one of TSR’s all-time greats. Don’t just read it. Run it!

Final Thoughts: Is C2 Still Worth Playing Today?

Alright, let’s talk honestly—is C2: The Ghost Tower of Inverness still worth playing today? Does it hold up? In my opinion, the answer is a resounding yes.

This isn’t a sprawling, open-ended epic. It’s not a political intrigue sandbox or a narrative-driven character drama. It’s a gauntlet. A puzzle box. A pressure cooker wrapped in deadly traps and strange logic. And that’s exactly why it holds up. The Ghost Tower is designed to challenge the players, not just their characters. It demands creative problem-solving, tight teamwork, and a good helping of old-school caution. Run recklessly, and it will eat your party alive. Play smart, and you’ll feel like geniuses by the end.

As for converting it to modern systems? It’s surprisingly painless. Old-School Essentials runs this thing right out of the box with almost no tweaks. For more modern systems, you’ll need to adjust monster stats and maybe smooth over some of the rougher tournament edges, but the bones are rock-solid. In fact, I’d argue that Ghost Tower works even better in a modern table with players who think they’ve seen it all. There’s something deeply satisfying about watching a new set of players get completely blindsided by a reverse gravity puzzle or a medusa in a rose garden.

So yes, if you’ve never played this one, you owe it to yourself and your group. It’s a classic for a reason. This one’s earned its place on the Dungeon Magazine’s “Top 30 D&D Adventures of All Time.”

But I want to know what you think! Drop a comment below and let me know what you think of Dungeon Module C2: The Ghost Tower of Inverness. Do you own it? Have you played through it? Have you run it? What did YOU think? Let me know!

And hey, if you don’t own it, good news! You can grab a copy of Dungeon Module C2: The Ghost Tower of Inverness in print or PDF at DriveThruRPG!

Okay, that’s gonna do it for today stat-rollers! If you’ll excuse me, I’ve got to go reread the part where the Soul Gem vaporizes a PC’s soul in front of their horrified friends. Never gets old.

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