First try at an old school dungeon

[Thrudd]

This seems to take things a bit far. Negative reviews can be useful, and if the standard of reviewing is only reviewing things that are enjoyed, they are going to become pretty scarce.

I think it would be more accurate to say that you shouldn't review a product that you aren't willing to use in the way it is meant to be used. If you are going to review a game module, you would need to play the game it was intended for in the way it was intended to be used. Otherwise, it might be a review of whether the old game modules work as self-contained story game adventures for modern-style games. The answer, of course, is "no" in almost all cases.

Certainly, every module will not appeal to every DM's game style, either mechanically or aesthetically. But it is not fair to judge them at all unless you are playing the game they were intended for.

Old D&D is a game where players seek out adventure and treasure in the sorts of places the modules provide. If your game is not about seeking treasure in monster filled dungeons and wildernesses (for whatever reason), then you are not playing the game these modules were designed for.

[1eGuy]

Old D&D is a game where players seek out adventure and treasure in the sorts of places the modules provide. If your game is not about seeking treasure in monster filled dungeons and wildernesses (for whatever reason), then you are not playing the game these modules were designed for.

And cities, of course. Lots of city-based material was released for D&D and of course the genre it was based on (Lieber, Howard etc.) had plenty of source material centred around cities. CSIO is probably the single best thing ever released for D&D and I would haul my copy out of a house fire before my copies of the OD&D/AD&D rule books.

[Jay R]

This seems to take things a bit far. Negative reviews can be useful, and if the standard of reviewing is only reviewing things that are enjoyed, they are going to become pretty scarce.

I apologize; I failed to explain my point well.

You should not review specific items in a class that you don't enjoy, because you aren't likely to be able to tell good ones from bad ones.

I love old swashbuckler movies. Therefore I can reasonably tell the good ones (Errol Flynn, Tyrone Power, Douglas Fairbanks) from lesser ones (Louis Hayward).

But I don't enjoy old detective movies. So I wouldn't be able to tell the good ones from the bad ones. But other people do enjoy them, so I recognize this as a matter of personal taste, not that all old detective movies are garbage.

Similarly, if you don't like old-style dungeon crawls, then don't play them. But recognize that since other people do enjoy them, this is a matter of taste, not that they are all garbage.

In any event, I hadn't realized that he was the original poster. He doesn't like them, so he's experimenting to see why. That's a valid experiment, and I withdraw my objections.

[Knaight]

I apologize; I failed to explain my point well.

You should not review specific items in a class that you don't enjoy, because you aren't likely to be able to tell good ones from bad ones.

I'd consider this a much better position, though I'd still disagree. To use a fairly extreme example - I'm not fond of diseases. I do have a fairly strong interest in the subject, but there's no disease I actually like. With that said, that doesn't prevent me from being able to look at diseases and evaluate them. There are still useful criteria - virulence, lethality, ease of transmission, presence in animal hosts, ease of treatment, etc. I wouldn't want to deal with either anthrax or the black plague, but as the latter has much more restrictive transmission methods and is a lot easier to treat, it's less worrying.

The same thing applies to media. I might not particularly like romance novels, but I still have enough training in literature to do some looking into which are good, and which are crap. Even without that training, basic things like plot consistency, character development, and very basic word use are plainly visible.

Modules are an odd case here, in that formal training doesn't really exist. That said, I would say that it's very possible to evaluate modules that are in a style that one dislikes. I'm not fond of the linear story, low player agency type of modules, but I can still distinguish the ones where the players are taken through an incoherent mess from the ones where the players are taken through a sensible scenario where things proceed in an understandable way. I'm also not too fond of dungeon crawls, but that doesn't mean I can't tell the difference between well thought through ones which are interesting and boring ones with no creativity featuring a bunch of featureless rooms with boring groups of enemies.

[rredmond]

Interesting thread.

Not really answering the OP per se, but here's a good example of an old school dungeon:

http://www.and-mag.com/category/blog...iskelion-blog/

It's free to download and check out too.

But do what you think will be fun to create and for your players. It'll be great I'm sure.

Be well,
--Ron--

[kyoryu]

This seems to take things a bit far. Negative reviews can be useful, and if the standard of reviewing is only reviewing things that are enjoyed, they are going to become pretty scarce.

I think it's a matter of category, and whether you dislike an entire category of things.

I like pizza. A bad review of pizza from my may be just as interesting as a good one.

I despise mustard. It is the unholy excrement of demons. There is nothing useful to be gained from me reviewing any type of mustard, as it really brings no new information to the table.

[rredmond]

I think it's a matter of category, and whether you dislike an entire category of things.

I like pizza. A bad review of pizza from my may be just as interesting as a good one.

I despise mustard. It is the unholy excrement of demons. There is nothing useful to be gained from me reviewing any type of mustard, as it really brings no new information to the table.

Very good point! When I know someone likes the "category" of what they are reviewing (usually RPG products) then I can glean whether I might like the product or not from both positive and negative reviews.
--Ron--

[Jay R]

I'd consider this a much better position, though I'd still disagree.

It's the same position; we just didn't communicate the first time.

Modules are an odd case here, in that formal training doesn't really exist. That said, I would say that it's very possible to evaluate modules that are in a style that one dislikes. I'm not fond of the linear story, low player agency type of modules, but I can still distinguish the ones where the players are taken through an incoherent mess from the ones where the players are taken through a sensible scenario where things proceed in an understandable way. I'm also not too fond of dungeon crawls, but that doesn't mean I can't tell the difference between well thought through ones which are interesting and boring ones with no creativity featuring a bunch of featureless rooms with boring groups of enemies.

All of this is true, and all of it is irrelevant. I objected to somebody stating that "all TSR modules are garbage (with one trifling exception)."

That's the kind of negative statement I disapproved of. Since they were popular, and sold well, and helped the hobby grow, they are clearly not all garbage. They are just the kind of thing he didn't like.

[Yora]

Which is perfectly reasonable, but quote correctly:

I think all TSR modules are complete garbage, except for G1-3. But perhaps this may be because I would play them wrong, so I want to try what happens if you run a dungeon like the people say it's supposed to. The setup for the next adventure seems like a good opportunity to test that.

And consider the context:

If you want it to be "oldschool" you want random rooms in a random layout with essentially random monsters, possibly on a theme. :P

If you want it to make sense, you probably don't want any of those things.

You can freely replace "I think" with "it appears to me", but otherwise I still regard it as a valid statement.

And it wasn't a review but an elaboration on why I believe I require more understanding of the subject.

[hamlet]

So! How's the Old School Dungeon coming?


</big booted attempt to change subject>

[Yora]

It's just dungeon now. The "unique" traits that are popular primarily among oldschool grognards are of no interest to me. The traits of other dungeons from oldschool modules are used by basically everyone, regardless of rules style they prefer.
So just dungeon.

However, there is one type of dungeon I only remember seeing in published adventures by WotC and Paizo. Which would be the linear story dungeon. These dungeons tend to have only one possible route of passage, that may on occassion split up for a short distance before it remerges, and has the purpose that the big bad of the dungeon is in the very last room the PCs can possibly reach. Videogames also do that all the time.
That's something I would avoid at any cost, and which to my knowledge was never done in any OD&D or AD&D 1st edition module. But calling any dungeon that avoids that oldschool would be stretching it too far, It's just good design that benefits all games.

However, one aspect of the linear dungeon is, that everything in it must be defeatable without too much trouble by the party. If they back off or don't want to fight, the adventure can not continue. In a dungeon with multiple paths only a single possible route must be easy. All the other encounters could possibly be too difficult for the party, unless they get creative. And encounters that should better be avoided is certainly something that is very rare, if not unheard of,outside of oldschool games. Could be done in any d20 game as well, but it doesn't seem to be a common assumption.
Same goes for wandering monsters, which just don't make sense in a linear dungeon and would only be pointless padding, if there is no way to avoid them.
Okay, so maybe still quite oldschool.

[kyoryu]

I think the main features of an old-school dungeon really boil down to the main points of old-school play:

Exploration: Figuring out what's in the dungeon.
Resource management: getting in and out without dying, management of food supplies, etc.
A "living" world: This is the biggie - the dungeon shouldn't just wait for you to ransack it. Enemies should run when appropriate, alerting others, etc. Make friends with one faction in the dungeon, and try to get them to ally with you against the others.

If you're running an old-school dungeon "right", it's not just a list of rooms to ransack. It's almost a living, breathing entity itself, one that is hostile to your presence. There's a reason this kind of play is often called "Fantasy Vietnam". Avoiding conflict is often better than engaging in it. Think more "Ocean's Eleven" and less "Rambo".

[Yora]

Except the first Rambo.

Supplies are a good point. Since the adventure I am working on for tomorrows game is basically being trapped in a labyrinth, running out of supplies should become a major issue. After all, some of the other creatures in the cave primarily want to steal the PCs food.
But I have a hard time making that relevant. They would have to stay for three days or more before lack of food becomes a real problem. However, torches would probably become a problem much quicker. Since the players will have tracked their target to a cave, I predict that they will rest after the long hike and enter it only the next morning. They have him cornered and there is no way for him to get past them if they camp at the entrance. That means they almost certainly won't make camp inside the cave and instead attempt to deal with everything in one go. How do I make supplies matter in such a situation? Letting them go in circles for hours encountering nothing until they are too tired to continue doesn't sound fun.

I just realized that though the gnome scout won't be with the party this time, one of the priests found a mask that allows him to see in the dark. That could get very interesting when everyone else is blind.

[Thrudd]

Except the first Rambo.

Supplies are a good point. Since the adventure I am working on for tomorrows game is basically being trapped in a labyrinth, running out of supplies should become a major issue. After all, some of the other creatures in the cave primarily want to steal the PCs food.
But I have a hard time making that relevant. They would have to stay for three days or more before lack of food becomes a real problem. However, torches would probably become a problem much quicker. Since the players will have tracked their target to a cave, I predict that they will rest after the long hike and enter it only the next morning. They have him cornered and there is no way for him to get past them if they camp at the entrance. That means they almost certainly won't make camp inside the cave and instead attempt to deal with everything in one go. How do I make supplies matter in such a situation? Letting them go in circles for hours encountering nothing until they are too tired to continue doesn't sound fun.

I just realized that though the gnome scout won't be with the party this time, one of the priests found a mask that allows him to see in the dark. That could get very interesting when everyone else is blind.

You don't need to make supplies matter, the rules of the game make supplies matter. If the players are cautious and bring a few days worth of supplies into the cave, then they probably won't have a problem. If they rush into the cave without enough supplies and get lost, then they have an issue. They are in charge of planning the expedition and packing supplies, right? Let happen whatever happens, and let them use their wits to overcome whatever problems they encounter.

Also, why would they go in circles for hours without encountering anything? There are wandering monsters, right?
You have to allow the chance that they fail. Why else would you design a labyrinth like this? It is a challenge that the players will overcome, or they won't. That's how you run an old-school dungeon. It's tricks and monsters may be dangerous, but they are solvable with wits, guts, and luck.

[Yora]

Not encountering anything would be a worst case of dragging out time to get them tired enough to make camp. Which I didn't actually consider. It was just a bad example.
There will be running water (since the longtime captives need to drink regularly), so water won't be an issue. Likely they won't stay for more than a few days, so food also won't be a problem.
The other main resources they have are light and spells. The players never have been big about carrying a supply of torches and they won't know the person they are chasing is running into a cave, so this one will most likely come to bite them in the ass. One of them has a magic mask that can see in the dark, so they won't get completely screwed. I think a few caves will have glowing fungus, which would be the places where the creatures without the ability to see in darkness like to hang out. An oasis of light, so to speak. And there will be lots of bats. Not exactly sure how realistic that is, but it burns and can be the main surce for fires in the caves with no wood around. If they will run out of magic and decide to camp, I don't know. They have been very frugal with their few 1st level spells and always cleared all places in one go.
Are there other limited resources I should keep in mind?

[Thrudd]

Not encountering anything would be a worst case of dragging out time to get them tired enough to make camp. Which I didn't actually consider. It was just a bad example.
There will be running water (since the longtime captives need to drink regularly), so water won't be an issue. Likely they won't stay for more than a few days, so food also won't be a problem.
The other main resources they have are light and spells. The players never have been big about carrying a supply of torches and they won't know the person they are chasing is running into a cave, so this one will most likely come to bite them in the ass. One of them has a magic mask that can see in the dark, so they won't get completely screwed. I think a few caves will have glowing fungus, which would be the places where the creatures without the ability to see in darkness like to hang out. An oasis of light, so to speak. And there will be lots of bats. Not exactly sure how realistic that is, but it burns and can be the main surce for fires in the caves with no wood around. If they will run out of magic and decide to camp, I don't know. They have been very frugal with their few 1st level spells and always cleared all places in one go.
Are there other limited resources I should keep in mind?

Not really. Maybe arrows/missile ammunition. Are you using the rules as written for HP recovery? That is the biggest resource that limits time spent in the dungeon. 1 HP is recovered per full day of rest. That's 24 hours, not 6-8 hours of sleep. If they can't find the way out quickly enough and are injured, this will be their biggest concern. They will need to come up with a solution that will let them rest in the caves without threat of molestation in order to recover spells and HP. If your design makes this easy, they will probably have no problems with spells or HP, only running out of food and torches will force them to get creative. If it is impossible to rest anywhere in the caves and impossible to leave without finding their target, there may be a good chance of deaths even before they need to worry about running out of food and light.

[Yora]

Good point. They don't necessarily have to be unable to rest, it would already be enough if the players feel that it is unsafe to do so. If they go through some trouble to find a reasonably safe hiding spot and setting up alarm traps or the like, it will already be a meaningful addition to the game.

I think this is already a quite decent adventure, that I have ready. But one thing I'd like to add would to have a few more traps set by the inhabitants of the caves, and maybe a few natural obstacles as well.
I have one room filled up to the hips with carbon dioxide and some other vapors to make it visible. Anyone who goes to the ground has to make a saving throw or pass out from lack of air and suffocate after a few minutes. When you kneel down to check on them, you're also breathing it. (If all fall unconscious, the wandering trolls happen to come by and take them prisoners to eat later.)

[Yora]

Ran the dungeon today. Here is how it went: Link

Took about three hours and the players seemed to have lots of fun. Even though I still had pretty much no discriptions for the rooms and never really thought how the creatures would react until the encounter started.
The ogre mage was indeed the toughest fight, but they had all the allies they could possibly get and they chose to attack it. That's how I had intended it. And in the end, they were already saying how much they would be bragging about those fight to the two players where didn't play today.
The story with the two trolls was also quite cool, I think I give a few extra XP to the player who had the idea.

Could all have been much better run and much better prepared, but as my games go, I think this went really quite well.

[kyoryu]

I know you've already run this, just commenting on the design thoughts... glad it went well!

Not encountering anything would be a worst case of dragging out time to get them tired enough to make camp. Which I didn't actually consider. It was just a bad example.

Yeah, if you're running an old-school dungeon, you don't really worry about pacing or stuff like that. You let the players decide how far they do or don't want to go.

If they will run out of magic and decide to camp, I don't know. They have been very frugal with their few 1st level spells and always cleared all places in one go.

Then either they're going into small places or the opposition is too easy? :D

If they camp, they camp. Let them make their preparations, and roll random encounters as appropriate. Just because they're sleeping doesn't mean the dungeon is. And any intelligent critters wandering about will certainly notice that their friends are missing, and that there's this door that's strangely spiked shut.

Good point. They don't necessarily have to be unable to rest, it would already be enough if the players feel that it is unsafe to do so. If they go through some trouble to find a reasonably safe hiding spot and setting up alarm traps or the like, it will already be a meaningful addition to the game.

Yup. Camping in the dungeon should be a choice, albeit a *scary* one. My understanding of Gygax's games is that it just wasn't done.

[Thrudd]

Ran the dungeon today. Here is how it went: Link

Took about three hours and the players seemed to have lots of fun. Even though I still had pretty much no discriptions for the rooms and never really thought how the creatures would react until the encounter started.
The ogre mage was indeed the toughest fight, but they had all the allies they could possibly get and they chose to attack it. That's how I had intended it. And in the end, they were already saying how much they would be bragging about those fight to the two players where didn't play today.
The story with the two trolls was also quite cool, I think I give a few extra XP to the player who had the idea.

Could all have been much better run and much better prepared, but as my games go, I think this went really quite well.

Sounds like a good time for everyone, well done. I am surprised nobody was killed by the Ogre's cold blast, as it sounded like they were already weakened from their fight with the troll. Were they just really lucky, or did you reduce the Ogre's power? Also, what level were those NPC's? It seems crazy that not a single one was taken down, they must have been scoring a lot of hits with their arrows.

Also, the 1e rules by the book say that when you are brought to 0 HP or lower and then revived you will still be in a coma for 1-6 turns (10-60 minutes), and then require a full week of rest in order to do anything other than slowly walking, eating and sleeping. Healing will keep you from dying, but it won't get you back in the fight or let you continue adventuring. You will need to be slowly escorted or carried from the dungeon and given a safe place to rest for a week. Does the retro clone you are using have this rule, too?

[Yora]

Maybe... I'm not sure. I read that part of the rules once, but don't remember anything like that. I'm mostly running on defaults from 3rd edition for such things.

The ogre mage was basically a custom creation.

Spoiler

Show

Oni
No. Encountered: 1d6
Size: L
Movement: 40
Dexterity: 11
Intelligence: Average (8-10)
Armor Class: 4 (15)
Hit Dice: 5d8+2 (24 hp)
No. of Attacks: 1 (weapon)
Damage: 1d12
Saving Throw: 14
Morale: 10
Experience Points: 620

• Oni can cast fly (12 minute duration), invisibility, darkness
and alter self at will. Once per day, they may also use
charm, sleep, wraithform and cone of cold as a 5th level
spell caster.
• Oni regenerate 1 hp per round.
• Cold, electricity, and fire attacks inflict 1⁄2 damage, or 1⁄4
damage if save is made.

For magic I basically use the 3.5e psionics system. He rolled a 15 on his 5d6 damage and the PCs both failed their saving throw for half damage. The only real difference to AD&S seems to be that he does not do 8d8 damage with the cone of cold. That would have most probably instant killed them, even on a successful save.

[Yora]

I got another question, though.

The players left the cave with the ogre mage trapped inside, and planned to return next time with the full party of 5. They pretty much killed everything in the cave and led all the trapped people out, and explored all but 2 areas.
This is a situation that should come up in dungeon crawl campaigns all the time. Are there any good ways to make the most of it as a GM. Just walking to the lair and having a single fight wouldn't be too particularly exiting.

Given that they go there with the specific intent of hunting a monster and slaying it, there could be enough fun in simply trying to find a way to keep it from running away, which their magic powers make them really good at. Gaseous form, fly, invisibility, and darkness are great spells for that purpose, and it only needs minute or two to heal all its wounds. But any ideas how to spice it all up?

[Knaight]

Having the ogre mage try to bail is a good idea - particularly as their spells (particularly wraithform) are pretty suitable for escape. If the ogre mage can escape the traps and get out, it could be interesting to have the characters go into the cave, enter the area, and find it vacant.

[Yora]

The deal with this particular cave is that nobody can get out without a unique magic amulet, which the PCs possess. The ogre mage now knows that they were able to leave and that they took some of the people that were trapped with him with them. Now when they return, he will be certain that they have a way to leave cave, which could be the key to his freedom.
The PCs will try to find and corner him, while he will try to evade them, but also follow them undetected. This might be his last chance to ever get out again.

Since they didn't cause him any permanent injuries, he also might attempt to make a bargain for his freedom. But so far the group has been very trigger happy and attacks first and asks questions later, so he would have to have a really good offer.

That is, if they can corner and defeat him, which is far from a given.
Just trying to find an invisible flying enemy in a large labyrinth could get a bit boring, and the players don't know he has either of these abilities. Instead of having them stumble around blindly, the ogre mage could set up traps in anticipation of their return. The resources he has are plenty of water, huge amounts of bones, fresh corpses of various creatures, carrion crawler poison, and glowing fungus. There is also a room filled to the waist with carbon dioxide, which makes everyone who breathes it faint after two rounds or so. That would be a perfect spot for tripping traps.
I think this could actually become a really cool mini-adventure.

[1eGuy]

I got another question, though.

The players left the cave with the ogre mage trapped inside, and planned to return next time with the full party of 5. They pretty much killed everything in the cave and led all the trapped people out, and explored all but 2 areas.
This is a situation that should come up in dungeon crawl campaigns all the time. Are there any good ways to make the most of it as a GM. Just walking to the lair and having a single fight wouldn't be too particularly exiting.

Given that they go there with the specific intent of hunting a monster and slaying it, there could be enough fun in simply trying to find a way to keep it from running away, which their magic powers make them really good at. Gaseous form, fly, invisibility, and darkness are great spells for that purpose, and it only needs minute or two to heal all its wounds. But any ideas how to spice it all up?

What would you do if the ogre mage was your character? Would you go for the stand-up fight, or try to get out of your prison?

I'd bet on the latter, in which case the polymorph ability is the one to go for, pretending to be a human (left behind in one of those two areas) and joining the party to investigate how they are able to leave and hopefully use it to trap them in there while you get out and away. A well-placed charm person when the party are resting and there's just a single guard on watch should be a potential bomb in their plans.

Has the party any way to penetrate such a disguise, and if so does the OM know about it?

[Yora]

Pretending to be human and using charm person seem to be the obvious first two choices. But he ca charm only once per day, and it will only work if he can catch one of them alone. Both are worth a shot, but not enough, given the risk of remaining trapped forever. To add to his disguise as a human, he will pick up the discarded backpack at the ghouls lair. Since I described it as having a ripped strap when the players took the rope and torches from it, this will also be a detail in the description of the man they encounter. It will probably be two weeks until our next game, but maybe someone notices it.

He only knowa that they have a way to leave, but not how. So it is vital that he can get at least one prisoner to tell him. Simply staying close to them while invisible would be enough to leave, but he doesn't know that either. So anything that could kill allof them would be out. The poison from the carrion crawlers would be perfect for that.

I would also love to do something cool with the corpses of the trolls and the ghouls. The players don't know they killed all that were in the cave. Maybe put them like they are sleeping and place set alarm traps when anyone sneaks up to sneak attack them.

[1eGuy]

Pretending to be human and using charm person seem to be the obvious first two choices. But he ca charm only once per day, and it will only work if he can catch one of them alone. Both are worth a shot, but not enough, given the risk of remaining trapped forever.

His polymorph power is pretty good since he can use it at will and also has gaseous form. Once again, joining the group seems a good move. While they're bedded down, he can GF out of his bedding and appear down the corridor as himself or a troll etc. and cause any number of distractions before returning in GF or invisibility. Sleep cast on the group while they're actually sleeping has potential too.

Also don't forget that darkness doesn't have to be centred on oneself; it can be placed down a corridor or even onto an item one of the PCs is carrying; again causing confusion. Once the OM knows what opens the exit, I'd imagine his one aim will be to separate that amulet from its current owner and scat. If he can split the party and quickly fall on the amulet holder his distant evil laughter might be the last thing the party ever hears....

Ogre Magi are tough opponents due to their abilities in general and the regeneration in particular, but this one doesn't look to be enough to fact the party in a toe-to-toe fight (what level are the PCs?). So the return to the maze should be much more like "Alien" than "Aliens"

[Thrudd]

I got another question, though.

The players left the cave with the ogre mage trapped inside, and planned to return next time with the full party of 5. They pretty much killed everything in the cave and led all the trapped people out, and explored all but 2 areas.
This is a situation that should come up in dungeon crawl campaigns all the time. Are there any good ways to make the most of it as a GM. Just walking to the lair and having a single fight wouldn't be too particularly exiting.

Given that they go there with the specific intent of hunting a monster and slaying it, there could be enough fun in simply trying to find a way to keep it from running away, which their magic powers make them really good at. Gaseous form, fly, invisibility, and darkness are great spells for that purpose, and it only needs minute or two to heal all its wounds. But any ideas how to spice it all up?

Have they literally explored every corner of the caves already? If so, maybe you add on a section which they "missed" last time. You've got two weeks to prep. Maybe there was a concealed passage or secret door that they passed by last time which they now notice, maybe there's a few of them. A whole extra section with more creatures living in it, more treasure, more long lost adventurers.

The Oni should definitely use it's abilities to infiltrate the group and figure out how to escape. At the very least, follow them invisibly for a bit, wait for a good opportunity to polymorph and join the party as a lost human. He could even lie, and tell them that he saw the Oni get eaten by another creature, so maybe they'll give up the hunt and just show him the way out. Or ask them to show him the way out before they continue the hunt, because he has been lost for so very long and wants to find his family.

[Yora]

I could expand the dungeon and add more rooms and creatures, but would that really be either a good idea or neccessary? I'm a frequent user of Schrödingers Gun, rewriting and switching things the PCs have not interacted with yet. If they will never know, there is no harm in changing things retroactively.
But I think there might be some benefit in having the players see that the world is as it is and they are exploring it, rather than everything coming into existance to entertain them. If they return and discover that there was only one more empty room, I think this can have quite some effect to how they approach exploration in the future. They learn that they can make poor and boring descisions.
If they were returning to search for more treasure, I probably would just tell them not to bother and jump straight into the next adventure. But this time they plan to come back for a monster hunt, trying to slay a creature that they already know to have formidable strength and magical powers. And it's a goal which they have set for themselves, which I also want to very strongly encourage them to do in the future. I think keeping things as they are and not introducing any new elements would be the better way to progress here. That they are familiar with the layout is an accomplishment of their last adventure, and I don't want to take that away from them.

I think when it comes to interactions with the ogre mage trying to decieve them, I'll make things up as I go. He isn't that particularly smart anyway, and doesn't really know much about the PCs and their intentions. He doesn't need a super-detailed plan to cunningly outsmart them.
But he has a chance to prepare the battlefield in his favor. We didn't really have any traps in the previous dungeons, and since this one is going to be a cat and mouse game, dirty tricks are both fair game and won't be slowing down the adventure. The players may not realize it yet, but they have signed up for The Most Dangerous Game. And they will have to suffer the consequences.

I think I'll watch Predator again, and the Stonehenge Battle from Conan. Should be good ideas there.

[JustSomeGuy]

Maybe 'the thing' would have some ideas too, if he intends to split them and charm/polymorph his way to freedom?