Making a Demon Lord Encounter Fun

[pwykersotz]

So here's the setup. I am going to be running a fight against a custom demon lord very soon. His powers are so far pretty generic / undefined. Hordes of minions, two big and powerful servants, a human thrall, and a creeping doom that threatens to overshadow the land. The theme of the demon lord is roughly mirror-based, leaving me open to design around a mirror dimension if I choose, but it's not necessarily locked in.

Now here's the question. The party is level 16-17, and my goal is to design something that will be fun to play through over 2-3 sessions. If you were playing in this scenario, what do you think would be a fun challenge to overcome? Sneaking through a lair? Sabotaging the demon lord's power somehow? Fighting minions with unique powers? All ideas are welcome, from the dramatic to the absurd, from simple to complex, as long as they would be something that would capture your interest as a player.

[Aett_Thorn]

The Big Bad Demon Guy (BBDG) is actually the heir to the throne of a neighboring kingdom (or even the one that is endangered by the BBDG itself). A rival heir hired an evil Gnome Illusionist to "take care of him", and the Gnome managed to permanently Polymorph him into a Demon. Do the player characters kill the Demon, or do they try to free/restore him? If the players kill the BBDG instead of restoring him, the kingdom could be placed into chaos with no rightful heir.

Having parts of the dungeon be illusionary along the way may give the players reason to suspect that things aren't what they seem, or the BBDG might have some noticeable 'tells' that would give him away. The mirror theme is actually the doing of the Gnome, not the BBDG.

[Waterdeep Merch]

What if the demon lord was actually fictional, and the new one is a mirrored version of it possessing the body of the local king/prince/princess/inn keeper? It's slowly rebuilding the power the fantasy version the demon lord had, including his kingdom and armies. The trick to beating him isn't just in confronting and destroying him, but completing the story. The mirror demon knows that it is susceptible to the way it was defeated in the story, and is actively working against the party to stop them from creating the macguffin that can banish him and save the day.

[GorogIrongut]

Mirror based...

1. Use the party against themselves. So the Demon Lord may not be that strong... but to even get to him/her/it, they have to fight themselves to even gain access to his little demiplane.

2. Once there they find themselves in a creepy mirror maze (much worse than you would find in a circus). The mirrors are little changing portals (their edges fluctuate the colour spectrum individually). Create a puzzle/problem to help them figure out how to maneuver the mirror maze.
It could be something as simple as entering in order portals that are only prime colours. So every 'mirror' they enter that isn't RYB in that particular order, shatters. They take damage from the shards of glass and part of their image/soul that was trapped in the mirror in the moment it shattered disappears. I would represent this as their max hit points going down by one of their HD for each mirror that they incorrectly attempt to enter.

3. Once they manage to go R and then Y and then B, they find themselves transported to your Demon Lords inner abode. Here I would do a couple of things:
a. The Demon Lord has his own version of Mirror Image cast on himself. Instead of just 3 illusory duplicates, have the room be filled with copies of the Demon Lord. Only one of them is the real one. They all act like him. Basically they shouldn't be able to tell who is the real one and who is the fake without targetting it.
b. The Demon Lord doesn't actually have any significant attacks it can use against them. It takes no turn of it's own. It can't cause physical damage via melee attacks against them. What it does have is 3 reactions. In which it mirrors an attack that the party have used against it.

So say the wizard decided to hit half a dozen of the copies using the spell fireball. As it arcs through the air, it encounters a mirror. The fireball enters the mirror and continues out of it to hit it's targetted area. BUT... another separate fireball arcs out of the mirror and is targetted wherever the Demon Lord wants it to go.

The bard decides to cast Alter Memories on the Demon Lord... the same thing happens.

Disintegrate... the same thing happens.

3 reactions to be used against the party.

[PhoenixPhyre]

Do note that in the default setting, a party going against a Demon Lord (especially on his home turf) without direct divine aid is going to get rofl-stomped. Demon Lords are nearly equivalent to deities, and even 20th level PCs can't take on a deity without tricks (somehow finding an deus ex machina artifact that gives them a fighting chance, etc).

I'd rethink that--it's not a Demon Lord, but a high-ranking demon (somewhere around a Balor++). Have most of the encounters revolve around evading/eliminating chunks of his army and finding leverage to either banish him (if on the material plane) or destroy/imprison him (if in the Abyss). Remember, level 16-17 characters aren't gods. They're powerful, sure, but maybe have 9th level spells (if level 17 and full casters). One 9th level spell. Trickery and guile should be the orders of the day, not straight up fights.

[Unoriginal]

Do note that in the default setting, a party going against a Demon Lord (especially on his home turf) without direct divine aid is going to get rofl-stomped. Demon Lords are nearly equivalent to deities, and even 20th level PCs can't take on a deity without tricks (somehow finding an deus ex machina artifact that gives them a fighting chance, etc).

I'd rethink that--it's not a Demon Lord, but a high-ranking demon (somewhere around a Balor++). Have most of the encounters revolve around evading/eliminating chunks of his army and finding leverage to either banish him (if on the material plane) or destroy/imprison him (if in the Abyss). Remember, level 16-17 characters aren't gods. They're powerful, sure, but maybe have 9th level spells (if level 17 and full casters). One 9th level spell. Trickery and guile should be the orders of the day, not straight up fights.

Actually a Demon Lord can be dealt with by a high level party (17+), as shown in Out of the Abyss. As long as they don't have access to their boundless armies and their Abyssal layer's vast ressources.

So as long as the fight is in the Material Plane, it should be intense but manageable.


So here's the setup. I am going to be running a fight against a custom demon lord very soon. His powers are so far pretty generic / undefined. Hordes of minions, two big and powerful servants, a human thrall, and a creeping doom that threatens to overshadow the land. The theme of the demon lord is roughly mirror-based, leaving me open to design around a mirror dimension if I choose, but it's not necessarily locked in.

Now here's the question. The party is level 16-17, and my goal is to design something that will be fun to play through over 2-3 sessions. If you were playing in this scenario, what do you think would be a fun challenge to overcome? Sneaking through a lair? Sabotaging the demon lord's power somehow? Fighting minions with unique powers? All ideas are welcome, from the dramatic to the absurd, from simple to complex, as long as they would be something that would capture your interest as a player.


If you want to make the Demon Lord mirror-based, I would say that one of his powers should be he is able to turn into a buffed-up version of one of the PCs' builds, for two rounds, and then randomly change to another PC's build.

That'd let you do a "mirror match"/Soul of Cinder kind of fight, which the players could find cool.

As for one of the challenges, I would have the PCs go through a house of mirror filled with illusory doubles of themselves and shape-shifted demons disguised as the PCs, making it hard to see if you are hitting someone real or who are your allies

[pwykersotz]

The Big Bad Demon Guy (BBDG) is actually the heir to the throne of a neighboring kingdom (or even the one that is endangered by the BBDG itself). A rival heir hired an evil Gnome Illusionist to "take care of him", and the Gnome managed to permanently Polymorph him into a Demon. Do the player characters kill the Demon, or do they try to free/restore him? If the players kill the BBDG instead of restoring him, the kingdom could be placed into chaos with no rightful heir.

Having parts of the dungeon be illusionary along the way may give the players reason to suspect that things aren't what they seem, or the BBDG might have some noticeable 'tells' that would give him away. The mirror theme is actually the doing of the Gnome, not the BBDG.

I do love a good moral dilemma. And the wizard hiding behind the demon does make a good misdirect. Illusions do fit the theme and could get quite intricate and interesting. Any in particular that you think would be fun?


What if the demon lord was actually fictional, and the new one is a mirrored version of it possessing the body of the local king/prince/princess/inn keeper? It's slowly rebuilding the power the fantasy version the demon lord had, including his kingdom and armies. The trick to beating him isn't just in confronting and destroying him, but completing the story. The mirror demon knows that it is susceptible to the way it was defeated in the story, and is actively working against the party to stop them from creating the macguffin that can banish him and save the day.

I'm loving the story within the story. Any thoughts on what might be guarding the book?


Mirror based...

1. Use the party against themselves. So the Demon Lord may not be that strong... but to even get to him/her/it, they have to fight themselves to even gain access to his little demiplane.

2. Once there they find themselves in a creepy mirror maze (much worse than you would find in a circus). The mirrors are little changing portals (their edges fluctuate the colour spectrum individually). Create a puzzle/problem to help them figure out how to maneuver the mirror maze.
It could be something as simple as entering in order portals that are only prime colours. So every 'mirror' they enter that isn't RYB in that particular order, shatters. They take damage from the shards of glass and part of their image/soul that was trapped in the mirror in the moment it shattered disappears. I would represent this as their max hit points going down by one of their HD for each mirror that they incorrectly attempt to enter.

3. Once they manage to go R and then Y and then B, they find themselves transported to your Demon Lords inner abode. Here I would do a couple of things:
a. The Demon Lord has his own version of Mirror Image cast on himself. Instead of just 3 illusory duplicates, have the room be filled with copies of the Demon Lord. Only one of them is the real one. They all act like him. Basically they shouldn't be able to tell who is the real one and who is the fake without targetting it.
b. The Demon Lord doesn't actually have any significant attacks it can use against them. It takes no turn of it's own. It can't cause physical damage via melee attacks against them. What it does have is 3 reactions. In which it mirrors an attack that the party have used against it.

So say the wizard decided to hit half a dozen of the copies using the spell fireball. As it arcs through the air, it encounters a mirror. The fireball enters the mirror and continues out of it to hit it's targetted area. BUT... another separate fireball arcs out of the mirror and is targetted wherever the Demon Lord wants it to go.

The bard decides to cast Alter Memories on the Demon Lord... the same thing happens.

Disintegrate... the same thing happens.

3 reactions to be used against the party.

I really like point 3b as it relates to the rest of this. Powerful trickery and powerful attacks are too much and would probably feel like a slog. But powerful trickery combined with such a weakness sounds neat. And having it be entirely reactive (at least for this part) is clever and lets the players try all sorts of plans. What do you think should be done if the players are savvy enough to simply try to walk through the illusions until they find the real one after they figure out the pattern? Should that simply be a matter of time until success, or should there be another layer to it?


Do note that in the default setting, a party going against a Demon Lord (especially on his home turf) without direct divine aid is going to get rofl-stomped. Demon Lords are nearly equivalent to deities, and even 20th level PCs can't take on a deity without tricks (somehow finding an deus ex machina artifact that gives them a fighting chance, etc).

I'd rethink that--it's not a Demon Lord, but a high-ranking demon (somewhere around a Balor++). Have most of the encounters revolve around evading/eliminating chunks of his army and finding leverage to either banish him (if on the material plane) or destroy/imprison him (if in the Abyss). Remember, level 16-17 characters aren't gods. They're powerful, sure, but maybe have 9th level spells (if level 17 and full casters). One 9th level spell. Trickery and guile should be the orders of the day, not straight up fights.

I'm definitely in the camp that doesn't need Demon Lords to be the highest CR, they just need to be masters of their particular sin/conceit with regards to the multiverse. I'm aiming for around CR 22 here, which the party definitely has the resources to handle and which is still pretty darned strong. Also, he's not really on his home turf here, he's been summoned and is corrupting the land to become his home turf. That said, good points. Would you just run the army evasion/elimination straight, or would you use some specialized mechanics to let the players create a more specialized strategy?


Actually a Demon Lord can be dealt with by a high level party (17+), as shown in Out of the Abyss. As long as they don't have access to their boundless armies and their Abyssal layer's vast ressources.

So as long as the fight is in the Material Plane, it should be intense but manageable.




If you want to make the Demon Lord mirror-based, I would say that one of his powers should be he is able to turn into a buffed-up version of one of the PCs' builds, for two rounds, and then randomly change to another PC's build.

That'd let you do a "mirror match"/Soul of Cinder kind of fight, which the players could find cool.

As for one of the challenges, I would have the PCs go through a house of mirror filled with illusory doubles of themselves and shape-shifted demons disguised as the PCs, making it hard to see if you are hitting someone real or who are your allies

This is pretty clever, but it does sound tough to run. I've done the whole character-swap thing before, and it's a high cognitive load. What sort of misdirects would you suggest to make the issue challenging but not frustratingly difficult? I do like the "like the PC's but buffed up" encounter, that could work pretty handily.


I do appreciate the feedback guys, and I'd love more. My poor brain has run this campaign from levels 3-17 at this point and since I haven't had time to read any new books or peruse adventure modules to refresh my thoughts lately, these ideas are a real breath of fresh air. :smallsmile:

[PhoenixPhyre]

I'm definitely in the camp that doesn't need Demon Lords to be the highest CR, they just need to be masters of their particular sin/conceit with regards to the multiverse. I'm aiming for around CR 22 here, which the party definitely has the resources to handle and which is still pretty darned strong. Also, he's not really on his home turf here, he's been summoned and is corrupting the land to become his home turf. That said, good points. Would you just run the army evasion/elimination straight, or would you use some specialized mechanics to let the players create a more specialized strategy?


Might be good to mix the two strategies. Give some of his troops a weakness--they can be banished by X. Maybe they're summoned and controlled through special mirror-gates? Shattering them would eliminate that source of troops. Another group might be deluded mortals (brainwashed into fighting for the demon lord). Those can be cured/whatever. A third (his home guard) might be straight-up fights. Of course, if they're strong enough they could go straight for him, but I'd have him gain strength (somehow) from his troops. The more they can eliminate, the easier to kill him without interference. On the other hand, the more time they spend dealing with the minions, the stronger his foothold/corruption becomes. Let them choose how they want to do it. If the party has allies, they may be able to call in support for a distraction. Leave the options open and be open to paths you didn't foresee. Those are often the best ones :smallbiggrin:

Whatever the way, make it clear what the consequences of each approach are up front, even if it's a little meta-gamey. I'd hate to take what seems to be the logical way of doing things (and do so expeditiously) and find out that because we'd done that, the boss was now impossible (or way stronger than it seemed). Smells of gotcha DM'ing to me. Not that I think you'd do that, but perception is a powerful thing.

[GorogIrongut]

I really like point 3b as it relates to the rest of this. Powerful trickery and powerful attacks are too much and would probably feel like a slog. But powerful trickery combined with such a weakness sounds neat. And having it be entirely reactive (at least for this part) is clever and lets the players try all sorts of plans. What do you think should be done if the players are savvy enough to simply try to walk through the illusions until they find the real one after they figure out the pattern? Should that simply be a matter of time until success, or should there be another layer to it?

The quick and dirty answer is that I'd treat them like a mirror. So the player would walk through them... and as they did, the image would morph from that of the Demon Lord to an image of them. And then it would shatter. As mentioned in a previous point, the player would then suffer dX amount of glass damage and their 'reflection' would steal a small sliver of their soul resulting in their HP Maximum decreasing by one of their hit dice. This would obviously be treated like other instances of HP Maximum reduction.

Yes, I'm a fan of the old maori belief that pictures steal a portion of your soul. I just tweaked it for it to work with mirrors in this case.

Or....


The more detailed answer is as follows:

If the players realize that just walking through them works... the room goes dark. As in completely pitch, darker than dark could possibly ever be dark. It's at this point, where no light of any kind can enter (including magical), they realize that something does in fact hide in mirrors. And it's only possible to see it when there is no light possible from which to cast a reflection on the surface of the mirror.

The creature inside the mirrors is the real Demon Lord. Simply destroying his proxy and all of his mirror images leaves the party the success of having defeated the Demon Lord, without ever having actually faced it. The Demon Lord escapes to fight another day and they've been had... completely bamboozled.

First things that happen...
1. Anyone standing in front of a 'mirror image' can see the Demon Lord reflected out of the mirror. It's a light that's dank and dark and dirty. They can feel the actual corruption of their body just being in it's presence. But when I use the term light, it doesn't actually function like a light. There's no interposing your hand to shield your eyes from it. It doesn't act like a wave. It just emanates from the mirrors without shedding any actual light on the rest of the room. It passes through all matter except that of a deity's form.

To be in it's presence is horrifying. Include a VERY hard saving throw or become terrified (terrified is the term I use to describe frightening something that is immune to being frightened. In every other sense, the players count as being frightened).

Right now would be a REALLY good time to freak your players out by introducing Sanity Points. I want them to feel like they're facing something unknowingly ancient, immeasurably vast and so far beyond the comprehension of mortals that to brush against it is madness...

2. It's from this point that the players can choose one of three options... if things are dark, they can walk through the mirrors and actually speak with an avatar of this Demon Lord. They can reason. They can barter. They can trade. This should be incredibly difficult as their world views are so infinitesimal to it. It sees everything as it's everywhere. In the mirror. In the reflection on a pond. The reflection off of tears or the glint of an eye. This is an opportunity to lose their souls in exchange for something epic. Or they can play it safe and just try and get out of this alive.
They can also attempt to destroy the mirrors without actually touching them. The 'light' of the Demon Lord emanates from each of the mirror images and should be easy enough to target. Once removed, the lights go back on and they can target the pseudo Demon Lord. They leave with a very cold chill crawling up their spines realizing that they just got the attention of something very scary. Something that can watch them for the rest of their days.

If any of them have a patron. Some deity. Some higher power. Something with more power than them. That is capable of aiding them in this fight. Then after exceptional rolls (see divine intervention of a cleric), the deity/whatever comes down and places a shield around them. For the space of 10 rounds they are able to confront the avatar of the Demon Lord and have a chance of actually killing it without the intervention of the actual Demon Lord.

If they succeed in this task, I would begin the commonly trod path in Dnd. You can't kill a deity/demon lord of reflection and mirrors. Just like you can't kill a deity of shadows, war, death, etc. But what you can do is supplant it. Make it's powers your own. Have the Deity/Whatever who interceded tell them that they've begun walking a dangerous path, one that they can't stop. They're now numero uno on the Demon Lord's hitlist and it's only by quickly assembling a list of specialized and highly powerful magic items that they have a chance of defeating the Demon Lord. Cue a whole new set of death defying quests. They should be harrowing. Keep using the Sanity Points.



I personally would choose the latter path... but that's because I like my games dark and difficult.

[Dungeon-noob]

I'll admit i haven't actually played much 5e yet, but these are my 5 cents on what kind of abilities you could give him.

I like the previously mentioned reaction based style, so i came up with a few things that fit with that.

1. This one is for the troops you give him. All his troops, friends, brainwashed minions etc. all have mirror shields. Besides functioning as normal shields, they have one extra ability: by sacrifising the shield, they can reflect one attack, spell etc back at it's source. AOE is only negated, but everything else goes right back to sender, status effects included. This way the troops become more dangerous, and the players have more trouble quickly getting through them to their boss. After reflecting, the shield is immidiatly destroyed.

2. As having a bunch of mirror images out for a passive boss with a mirror theme sounds great, i second that idea and would like to try to expand opon it. You could do several things if the players attack/pass through them. You could have them explode in glass shards like the other mirrors for xdx damage. But if simple boobytraps seem to simple or if you've used that enough allready, then what you could also try is having each image that the party checks temporarily turn into a copy of the relevant player. For d4 turns, that image has the same stats, skills etc. of the player who attacked/checked the image, and fights them as such. After that time, the image dissapears, in a particular gruesome death image for said character. Have each death be different and brutal, and ask for fear checks every time.

[Waterdeep Merch]

I'm loving the story within the story. Any thoughts on what might be guarding the book?

The author, of course. He appears to be an old recluse that only wants to be left alone. He's originally from that mirror-verse, which was born of his desires, and was the hero of his story. He discovered, to his horror, that the demon lord was his reflection in that world, and that he would come back endlessly so long as the hero remained. So he left, hoping to bring peace to the world of his dreams.

The demon lord had other plans. Since the original hero refused to return, his remaining forces eventually found someone else who read the story and dreamed of their world. Their innate goodness once again mirrored itself in the demon lord, who had the dreamer imprisoned in the mirror-verse. Then, to get back at the original hero, he used the power of the imprisoned dreamer to enter the real world along with his forces.

As a product of dreams, the demon lord has to obey what the dreamer believes. This is why the demon lord is repeating himself- he's following the dreamer's understanding of him from the story. This makes him somewhat predictable and gives him some strange storybook weaknesses, though eventually the demon lord realizes this as well. At first he'll target copies of the book and anyone who knows the story, but eventually he'll realize he's got another source of power- the dreamer.

By making the new dreamer believe in the demon lord's power, he'll truly gain it. So any macguffin created by the original hero will eventually fail in their final confrontation in the face of the dreamer's fears. To truly stop him, the players will have to either return the dreamer to their world or convince them to be courageous in the face of the demon lord, making them the new hero of the mirror-verse.

Upon defeating the demon lord, the players will awaken around a campfire, the original hero just finishing telling the sequel to his original story. The adventure was one of their dreams, themselves the heroes of their inner world.

[pwykersotz]

All right guys, thanks to those of you who replied for the ideas. I'll be working on this some more, and I might have a few more offshoot questions to pose. And if anyone else has any other thoughts, I'd still love to hear them!