Note to all readers. This is an original adventure module designed for the Dungeons and Dragons game. This module is compliant with all Open Gaming License and D20 SRD regulations. If this sort of thing doesn’t interest you then you might want to click here.
This adventure is designed for game masters who run light hearted games, and is not intended for more serious campaigns. This adventure is best suited for third level characters, but would work with almost any level low enough to not be able to magically detect a shapechanger.
GM Background: This adventure is set in the Dwarven cavern of Glimmer. It is recommended that one or more characters be a Dwarf.
The Dwarven cavern of Glimmer is a great Dwarven city that houses nearly 1000 dwarves. They are famous for the amount of Ale they consume and also for their annual Drink-a-Thon in which they consume all remaining ale stocks on the eve before the next year’s supply arrives from the city of Rockhome. The dwarves here are famous smiths and miners and don’t brew much ale of their own, instead choosing to buy vast quantities of ale from the neighboring city of Rockhome.
Most of the people in the Dwarven lands venerate the Dwarven pantheon, although a few dwarves worship various human gods of smithing and drinking, and some practice ancestor worship..
General Adventure Outline.
The DM should quickly skim over the text to Dwarven Beerfest Part I before running this adventure.
The characters have been left to guard the empty Dwarven City of Glimmer while the residents of the city go out to search for their missing ale caravan. They are locked inside, but they are not alone.
Special Pre-Adventure requirements.
This adventure may or may not involve a doppelganger. It is up to the gamemaster. The gamemaster might decide to truly use a doppelganger, or to simply have the characters fears feed off of each other so they think that there is a doppelganger. The adventure can be run either way. It has been play tested both ways and the players had a great time in both situations.
Before the adventure begins ask each player to write down how they would deal with an attacker in a corridor, and then to pass over their character sheets to you. Then send them all on a pre-game break of some sort, so that you will have time to do some prep work.
Run each character in a fight against the doppelganger listed below. Assume the doppelganger is going to hide in a side passage and then jump out and try to sneak attack them. Run it so the doppelganger flees if it cannot quickly disable the character. You should end up with a few characters that the doppelganger easily overcame and at least one whom it fled from. It is unlikely that any of them would be able to defeat it on their own.
Once you have all your results choose an overtaken character whom a doppelganger would be able to mimic more easily, such as a fighter or a rogue. That character is going to be the doppelganger, but you are not even going to tell the player of that character until the time is right.
Choose another character who got away from the doppelganger, as the one who sets all the suspicions into motion.
Note that the doppelganger in question is not particularly interested in killing the party, it would rather capture them alive as a prelude to eventually taking over the entire city of Glimmer. He is not the only doppelganger hiding in the Dwarven city, there are several others as well. This is just the only one that should infiltrate the party. We will be using the other ones as well. Just differently.
Size/Type: Monstrous humanoid (Doppelganger) Rogue 3.
Hit Dice: 4d8+3d6+7 (37 hp)
Speed: 30 ft. (6 squares)
Armor Class: 16 (+2 Dex, +4 natural), touch 12, flat-footed 14
Base Attack/Grapple: +6/+8
Attack: Sap +9 1d6+2
Full Attack: Sap +9 1d6+2
Space/Reach: 5 ft./5 ft.
Special Attacks: Detect thoughts, sneak attack 2d6
Special Qualities: Change shape, darkvision 60 ft., immunity to sleep and charm effects, evasion
Saves: Fort +5, Ref +8, Will +7
Abilities: Str 12, Dex 14, Con 12, Int 12, Wis 14, Cha 13
Skills: Bluff +13*, Diplomacy +6, Disguise +12* (+14 acting), Intimidate +6, Listen +9, Sense Motive +9, Spot +9, hide +5, move silently+5, Use Magical device+4
Feats: Dodge, Great Fortitude, weapon focus sap
Possessions sap+1, potion of gaseous form, 1000 GP in gems.
If going with the non-doppelganger version of the module just skip any actual doppelganger attacks, but pass lots of notes to create suspicion amongst the party.
Text in BOLD is meant to be read aloud to the players.
Encounter 1. All alone.
The characters are left standing inside the city gates of a very empty Glimmer. As the dwarves march off, Dorn Wetbeard calls back, don’t worry lads, we will be back in 3 days, a month at the most, and mind the gates. You are about to ask for a clarification when you realize that the large stone gate to the cavern has begun to close.
The city gate is closing, characters who run outside will be essentially out of the adventure. Characters who remain inside will be locked in for the duration.
I provided no maps for this adventure as the play area is large and vast. Glimmer is a pretty big area with many caverns both large and small. Draw maps as needed, and use your best judgment.
The character you replace with the Doppelganger will be replaced between encounter 1 and encounter 2. The player need not be notified at this point. The replaced character will have been knocked extremely negative with subdual damage, and the doppelganger will have equipped itself with his equipment. The replaced character is safely hidden away in a rather distant cavern.
Encounter 2: Oy, what’s that clank?
It is getting fairly late in the evening of the first night. Overall guarding the Dwarven city is proving to be extremely boring. Wait, a minute, what is that clanking sound off in the distance, sounds like it might be coming from the next cavern over.
The clanking sound is nothing but a rat rooting around in a kitchen in the next cavern over, he was eating the remains of last night’s stew that is still sitting in a pot.
One of three things will probably happen here. Either the entire party will go to investigate, some of the party will go to investigate, or (unlikely) they won’t investigate the sound at all.
If only some of the party want to go investigate then describe the investigating characters making there way into the other cavern, and then request that everyone else leave the room. Don’t let the players change their mind on who is going, or anything like that. Just have the players who aren’t present leave the room.
If the entire party goes to investigate then they will return to find that all their fires have been extinguished while they were gone.
The rest of the night will pass uneventfully unless player actions dictate otherwise. Although you should have anyone on guard duty make spot and listen checks throughout the night.
Encounter 3: Wolf in the fold.
Notify the players that you are going to begin passing notes now and it may go on for the rest of the game. Tell them that they may certainly act on the information contained in them, and that some notes might give them instructions, and those instructions must be followed. It will all be explained in the end. Their notes are for their eyes only and cannot be shown to anyone else in the group.
Depending on your player group at this point they may or may not be paranoid about a shape shifter in their midst. If they are already taking about the idea then you may skip the rest of this encounter and go onto encounter 4. But play the rest of this encounter if they are not paranoid yet (unless of course you are playing the no-doppelganger option, in which case you could drop a hint yourself).
This event involves the doppelganger character lying to the rest of the party. INSERT PC NAME is the doppelganger, and INSERT SECOND PC is any prep caster that would be preparing their spells in the morning. Substitute weapon maintenance if there is no prep caster to frame.
As INSERT PC NAME was walking out of the privy you found INSERT SECOND PC waiting to use it. But then when you returned to the rest of the group you found INSERT SECOND PC sitting their preparing their spells. They couldn’t have possibly beat you back here, heck he doesn’t even have his shoes on yet.
Pass the SECOND PC a note saying that he has been sitting there the entire time.
Encounter 4: All hell breaks loose.
The players should likely drive all the action from here on out. Begin passing notes to the various players, mostly just saying that things look funny about different characters. Start having the players make sense motive checks when other characters speak (make the rolls for them though, just ask what their modifier is).
Before the action gets too heated take everyone’s character sheets away from each other. Tell everyone they can certainly make all their own D20 rolls, but that everyone’s bonuses might not be the same as everyone else thinks they are, and you will need to work the numbers yourself. Roll any damage or the like yourself.
Continue passing notes, and creating suspicion as much as you can. If they finally solidly figure out which character is the doppelganger then (and only then), should you pass them a note telling them to run away.
A fight may very well break out between party members. Remember that the doppelganger character does not have the same ability scores or class abilities that other characters have. This is why it is particularly important that you replaced a fighter or rogue. Since a spellcaster is far too easy to smoke out.
Encounter 5: Alls well that ends well, or is it?
The gates to the city open back up around noon and you are greeted my many dwarves and an entire caravan of ale. It seems that there was a bridge out and the caravan masters had to take a detour that delayed them significantly.
If the party did not get to loot the doppelganger’s magic sap then the dwarven clan leader presents them with a dwarven waraxe +1 for their service to the clan.
If the doppelganger escaped with all of a character’s gear then the dwarves will soon discover the wounded character and they will equip him with non-magical masterwork gear (anything the GM wants the player to have is allowed). One suit of armor, one shield, 1 melee weapon and one ranged weapon.
Wrapping up the adventure.
If the party smoked out the doppelganger then all is well and good. If not, well, we ended the adventurer with a PC replaced by a doppelganger. You might want to keep that up for a few adventures before the original character manages to catch up to the party. One playtest group ended up playing with the doppelganger for six months after this adventure,.