Happy Christmas from the Santicore!
This year, I participated in
Jez's Secret Santicore, and the random number gods paired me with someone who has trouble with secret doors, and so wanted some sample secret doors with concrete methods of activation and specific reasons to be in the dungeon.
(At least I think I got that right. If you happen to be the requester and find this doesn't suit your needs, feel free to comment — we do returns and exchanges here.)
Anyway, I made a table of thirty secret doors. 1-20 are "mundane," meaning that they use mechanical means, however improbable. 21-30 are magical, meaning that they use magic mechanisms or somehow require interaction with a supernormal creature, like a ghost or golem. They might need slight modification depending upon where you put them ("Why is there an assassins' training ground in the Temple to Love and Squirmy Little Puppy Dogs?"), but they should at least be good inspiration.
Feel free to peruse the table or roll a d30. If you just want a random mechanical secret door mechanism, roll a d20. If you want a random magical or fantastical secret door mechanism, roll a d10 and add 20 to the result.
Without further ado, the table:
1 - This door is hidden behind a statue of a local lust deity recessed into the wall.
The statue and the section of wall swing open, revealing a secret passage, when the lips are pressed.
Supposedly, supplicants were to kiss the statue, and variants with switches placed to simulate other sexual acts likely exist.
Characters searching the area might notice the seams in the wall or the pedestal around the statue’s base, or they might notice seams around the statue’s arms.
2 - This door is hidden behind a bas-relief depicting showing historical scenes from the local kingdom.
The door slides open when the reliefs of the rulers are pressed in order according to the chronological order of their reigns.
Characters searching the area might notice the seams around the bas-relief, or seams around the buttons on the bas-relief.
3 - This section of wall contains a mechanism with a switch that vibrates at a certain frequency.
It will slide open when a certain note is played, requiring either an instrument, a singer with perfect pitch, or an appropriate tuning fork.
Characters searching the area might notice the seams around this section of wall.
Characters with supernormal hearing might notice the reverberations in the wall, indicating the presence of some small, acoustic chamber.
4 - This section of stone wall has a switch disguised as a stone.
Pressing the stone causes the wall to slide open.
Characters searching the area might notice the seams in the wall.
5 - A fresco depicting a local deity will slide open when a particular tune (a hymn or paean, perhaps?) is played on a nearby pipe organ.
Characters searching the area might notice the seams in the wall.
6 - A nearby message admonishing the faithful to not fear evil is accompanied by a statue of a black dragon recessed into the wall.
Reaching one’s hand into its mouth will allow one to press a switch in the back of the throat, causing a nearby section of wall to swing open.
Characters searching the area might notice the seams in the wall.
7 - A statue of a local deity of peace, its arms outstretched, stands in a place of prominence in the room.
A wall panel slides open when at least twenty-five pounds of equipment are placed in its arms — roughly the weight of weapons enough for six or so people.
Modern adventurers might not put their weapons in its arms, but the old supplicants did so before entering the secret passage.
Characters searching the area might notice the seams in the wall, or they might notice seams around the statue’s arms.
8 - A bookcase or other large, heavy object sits in front of an open doorway.
Astute characters might note scuff marks on the floor or a slight breeze.
9 - Astute characters might notice that this wall is hollow when tapped, or that there are seams in the mortar.
A simple people, the builders of the dungeon just used a prybar to open this wall, which can slide aside when pressure is applied.
10 - A statue to a local folk hero or maimed deity sits in the room.
A ceremonial weapon of the type who originally wounded this figure rests somewhere nearby.
Recreating the legendary figure’s wounds with this ceremonial weapon — in the order they were received — causes the statue to rise on a pedestal into the ceiling.
The pedestal has steps so that characters can climb it as a ladder, literally ascending into the heavens with the passing of this entity.
Characters searching the area might notice the seams in the statue’s base, or that the figure’s wounds contain seams or buttons.
11 - An astrological diagram has several recesses where nearby stones can be placed.
Each stone has an astrological symbol on it.
Placing the stones to recreate the birth chart of the Chosen One causes the wall with the diagram to iris open.
Characters searching the area might notice the seams in the wall where each wedge of the diagram is in place.
12 - This emergency escape route was installed by a corrupt ruler who attempted to eradicate the influence of the old regime.
This figure’s final affront was to place a tapestry of the region’s founder over the escape route, so that he would have to cut it open in time of strife.
This escape route was never used, and has lain that way since the ruler was killed by the servants.
Characters searching the area might feel a slight breeze from the direction of the wall.
13 - A subterranean river and a broken waterwheel dominate this room.
Anyone fixing the waterwheel — or harnessing enough power to turn the drive shaft — finds that a panel in the far wall slowly rotates with the waterwheel.
Characters searching the area might notice the seams in the wall.
Some characters might just wonder what the waterwheel powered.
14 - This room in a military barracks features a relief on the wall depicting an example of a hated enemy (“The 304th Dwarven Legion will exterminate all bullywugs!”).
Hitting the appropriate locations as per the old drills causes the wall to slide open for about five seconds, long enough for a few people to go through.
The old idea was that a recruit showed a superior officer his training by rapidly attacking the target, causing the wall to slide open and allowing the recruit to enter the next room.
Astute characters might notice the seams in the wall or in the “pressure points” on the foe diagram.
15 - Two statues stand is this room, holding their swords aloft.
If their sword arms are lowered, a trapdoor will open between them.
Characters searching the room might notice the seams in the floor or on the statues’ arms.
16 - A tangle of rooms was used as a training ground for assassins, and only those who recalled the teachings of the order could pass to the next chamber.
This room contains a statue of a humanoid resembling a typical member of the town watch.
As a mechanical feature, it rotates to face the largest concentration of weight in the room, either looking at a closely-packed group or the heaviest person in the room.
This room and the surrounding hallways are fitted with highly-sensitive pressure plates, built in such a way that they may be mistaken for old, slightly loose stonework by those who do not know better.
Passing through the secret passage is simple — the subtle handholds on the walls allow initiates to climb without touching the floor.
A hidden wall panel slides open if weight is removed from the floor tiles for more than a minute.
Characters might notice the pressure plates in the floor or the seams in the wall.
Some characters might grow suspicious at the rotating statue, particularly if they are unable to detect magic emanating from it.
17 - Strangely, the same room has another secret door — those who can leap from the wall and twist the statue’s head as if snapping the neck before the statue rotates to face them cause a trapdoor in the ceiling to open.
The trapdoor stays open for five minutes before the assembly resets.
Travelers must possess their own rope and grapple — or just be able to jump or climb very well — in order to proceed.
Characters might notice the pressure plates or the seams in the ceiling, as well as the seam around the statue’s neck.
18 - A large statue of a cyclops dominates one wall of this room.
If someone scales the statue and depresses its eye, the statue animates in a mechanical fashion and smashes the wall next to it (it may also incidentally hit the person activating the statue).
Characters might notice several seams on the cyclops statue, indicating articulation, or they might notice that the wall is weakened or hollow.
It is highly likely that the dungeon designers meant this as an escape route or a place for something well-hidden.
Some artisans also leave little trinkets behind, so this little treasure room might only contain some bizarre little fetish or some such.
19 - A treasure chest in the room contains treasure, but it also contains something else.
If the lock is locked while the chest is open, the key will turn past the point when it normally stops, opening the false bottom of the treasure chest.
A ladder leads down into another section.
Though it is time-consuming to clear out the treasure chest, the designers felt that most tomb robbers are too greedy to look further.
Characters might get suspicious about the fact that the treasure chest cannot move, and some might notice something strange about the lock.
Others might notice the seam at the bottom of the treasure chest.
20 - This circular room has a bas-relief on the wall depicting a sea deity or a legendary seafarer.
The ship’s wheel on the wall can be pulled from the wall and rotated.
This will rotate the entire room, closing some exits but opening others.
Some variants may not rotate the room, but may instead raise a pedestal in the middle, revealing a spiral staircase leading downward.
Characters might notice seams in the bas-relief, or in the floor or ceiling.
This very well may lead to a shrine to the deity in question, or perhaps a subterranean, aquatic passage leading elsewhere.
21 - This section of wall is a bas-relief or fresco depicting a local deity or folk hero.
If the proper supplication is performed before the wall, it swings open.
Characters searching the area might notice the seams in the wall, or the subtle arcane iconography in the wall revealing its magic.
22 - This secret passage is activated by a nearby painting of a local foe (likely historical).
Staring into the eyes of the painting for at least a minute causes the nearby section of wall to recess into the ground.
Characters searching the area might notice the seams in the wall, or the subtle arcane iconography in the wall revealing its magic.
23 - This section of wall isn’t stone at all, but an ooze that has taken on a consistency appropriate for the nearby wall.
Applying the appropriate reagent causes the ooze to assume its normal state and move aside.
Setting fire to the wall (or otherwise attacking it) prompts the ooze to attack.
Astute characters might notice that the wall quivers slightly, or that the acoustics in the room aren’t quite right.
24 - This section of wall bears an emblem of a local mage’s guild or equivalent.
The wall disappears briefly when struck by a particular spell, such as magic missile.
Inner chambers require higher-level spells to activate.
Characters might notice the subtle arcane iconography in the wall revealing its magic.
25 - This section of wall depicts the local deity of slaughter.
Spilling blood on the image causes it to open.
Strangely, spilled blood soaks into the image and is absorbed.
Characters searching the area might notice the seams in the wall, or the subtle arcane iconography in the wall revealing its magic.
26 - Invisible, incorporeal ghosts guard a crypt in this room.
They will open a hidden wall panel to any whom leave offerings to them in excess of 100 gp worth of coins or goods.
Unscrupulous characters who detect the ghosts might coerce them with pain or magic instead.
Characters searching the area might notice the seams in the wall, or they might detect the presence of the ghosts.
27 - In a chamber dedicated to a local deity, an oddly-placed statue of an opposing deity is recessed into the wall.
A holy book of the local deity sits in the room; reading a passage wherein the deity defeats the opposing deity causes the enemy deity’s statue to recess into the ground.
Characters searching the area might notice the seams in the wall around the statue, or the subtle arcane iconography in the statue revealing its magic.
28 - A large, flaming brazier sits in the middle of the floor, generating light and heat.
Following the temple’s instructions to be purified by flame, anyone who actually leaps into the brazier finds only a moment of pain before finding it is just an illusion.
A trapdoor leads into the floor.
Characters searching the area might notice the subtle arcane iconography in the wall revealing its magic, or perhaps that an object near the flame is not scorched.
29 - A sundial sits in the center of this room, whose entire far wall is dominated by a scene from an historical battle.
Shining a light on the sundial to recreate the supposed time of this battle (“Ah, yes, I remember from my time at university that the Battle of Gloaming’s Dark supposedly happened around the fourth watch after midnight, hence the name.”) causes the far wall to recess into the floor.
Other dungeons may make use of this trick, using times important to the builders of the tomb.
Astute characters might notice the seams in the far wall, or the subtle arcane iconography in the sundial revealing its magic.
30 - Undead stand silent sentinel in this room, but do not attack unless they are attacked.
If they are commanded to open the wall — possibly by a command word issued elsewhere, or possibly just by someone commanding them to open the door — they will do so.
Characters searching the room might notice seams on the wall.
Suspicious characters might make note of the fact that there are undead guarding the room with no apparent purpose.
Some magi architects, not wanting to delve into necromancy, might use golems instead.