Roller Stairs

 

A staircase leads down into the darkness.

Mechanical Trap

One of the stairs has been replaced with a cleverly disguised roller. A DC 12 Wisdom (Perception) check reveals that the stair in question is slightly concave. When a creature steps on the stair, they must make a DC 14 Dexterity saving throw or fall down the stairs, taking 1d6 falling damage and landing prone at the bottom of the stairs. The roller can be disabled by wedging something into the side. This requires a DC 10 Dexterity check.

 

Two Part Door

 

A stout wooden door blocks the way.

Mechanical Trap

The wooden door is locked and stuck, requiring force to open it. However, the lower 1 foot of the door is a separate door that is also stuck. When the door is unlocked, it attaches a pin into the lower part, so they both open together. A DC 12 Wisdom (Perception) check will let a creature notice a hairline gap that runs across the door about a foot off the ground. Closer inspection will reveal that this part of the door is not attached to the upper part. The door requires a DC 12 Dexterity check with thieves’ tools to unlock. It also requires a DC 12 Strength check to force open. If the door is unlocked first, the strength check is at advantage. If the door has not been unlocked, a successful Strength check to open the door must be followed by a DC 12 Dexterity saving throw. Failure results in the creature falling prone into the next room. If the creature is aware of the lower door, they may attempt the Strength check to open the door with disadvantage to avoid having to make a saving throw for the lower part of the door. Disabling this trap requires nails and something to attach the two door pieces together, and can be done by spending one minute to do so.

 

Rusty Sewer Grate

 

A broken grate, big enough to crawl through, is at the base of the wall.

Mechanical Trap

The grate has been blasted open. Bits of twisted and sharp metal are exposed, but the hole is big enough to crawl through. Bits of sewage coat the exposed metal. A DC 14 Wisdom (Perception) check will reveal that the metal is slightly slimy. A successful DC 15 Medicine or Nature check will reveal that the slime carries sewer plague. Crawling through the opening requires a DC 12 Dexterity (Acrobatics) check for size medium creatures. Smaller creatures have advantage on the check while larger creatures have disadvantage. Failure results in 1d2 damage and the possibility of being infected, as per the sewer plague description. Disabling this trap can be done by cleaning the metal, which requires a disposable cloth and a successful DC 12 Dexterity check. If this check fails, or if the cloth is stored on a person, that person has the possibility of being infected.

 

A Tight Squeeze

 

A piece of metal partially covers a hole in the wall.

Mechanical Trap

The metal covers a small hole in the wall. It bends inwardly easily, but does not bend the other way. A DC 10 Wisdom (Perception) check detects the presence of a small pile of something shiny and gold in the back of the hole. A DC 12 Intelligence (Investigation) check reveals that the space between the walls and the metal is too small for medium or larger sized creatures. A medium or larger sized creature can squeeze through the opening, the metal bends out of the way easily. This creature will discover a small pile of gold coins. However, once the creature tries to leave, the opening is too small. In order to leave unharmed a creature must succeed at a DC 21 Dexterity (Acrobatics) check. Failure results in 1d4 slashing damage, and the option to push through with a DC 12 Strength check. If the strength check succeeds, the creature escapes but takes an additional 2d4 slashing damage, while on failure, the creature is trapped but still takes an additional 1d4 slashing damage. The metal can be pulled off from the outside with a DC 14 Dexterity check, but requires some kind of leverage tool, such as a claw hammer or a crowbar.

 

Open Portcullis

 

A thick stone archway marks the entrance to this hallway.

Mechanical Trap

The archway houses a portcullis in the ceiling. 30′ down the hallway, a concealed pressure plate causes the portcullis to close when it is stepped on. A DC 5 Wisdom (Perception) check spots the portcullis above the archway. Several wooden pikes on the bottom can be seen. A DC 14 Wisdom (Perception) check reveals seams in the mortar around the stones on the floor that outline a 3′ x 3′ pressure plate. When the plate is stepped upon, the portcullis slides shut. Those under it must make a DC 10 Dexterity saving throw or take 2d6 bludgeoning damage, and end up on a random side of the portcullis. Creatures within 1/2 of their normal walking speed distance may attempt to duck under the portcullis to the other side. A DC 15 Dexterity (Acrobatics) check is required to do so. Failure means that the creature ends up just next to the closes portcullis on the same side they started. The portcullis can be opened easily from the room above. However, from here, it can be lifted with a successful DC 20 Strength check, or destroyed. It has AC 15 and 30 hp. If the pressure plate is spotted, it can be easily avoided. Disabling it requires a DC 14 Dexterity check. Jamming the portcullis requires access to several boards, nails and a hammer and/or axe and requires a successful DC 14 Dexterity check.

 

Bear Trap Door

 

The door pull sits in an iron rimmed recessed circle.

Mechanical Trap

The door pull causes the iron to clamp shut like a bear trap. A DC 14 Wisdom (Perception) check reveals tiny, sharp ridges on the iron rim. When the door is pulled open, the creature pulling it must make a DC 14 Dexterity saving throw or take 1d6 piercing damage and becomes restrained. While restrained, the creature may not take any actions that uses the hand that is trapped. As an action, the trap can be opened with a DC 18 Strength. The trapped creature has disadvantage if performing this check. The iron trap can be disabled with a DC 14 Dexterity check with thieves’ tools. Failure results in the creature being subject to the trap effect.

 

Slip Pit

 

The hardwood floor in this hallway is highly polished.

Mechanical Trap

A pit is in the middle of the hallway. Just beyond the pit the floor is very polished and slippery. A DC 12 Wisdom (Perception) check reveals a 10′ x 10′ area outlined by seams in the floor. A DC 14 Wisdom (Perception) check shows that the 10′ x 10′ area just beyond the seams is more glossy than the rest of the floor. Stepping on the seamed area causes the floor to open up into a 20′ pit. Creatures in the 10′ x 10′ area must make a DC 14 Dexterity saving throw or fall into the pit, taking 2d6 falling damage. A creature that jumps over the pit lands on the slippery floor and must make a DC 16 Dexterity saving throw, or fall back into the 10′ x 10′ area above the pit. If the trap door is opened, the creature falls in as above. Otherwise, the creature must make a DC 14 Dexterity saving throw at disadvantage, or fall into the pit. A creature climbing out of the pit must make a DC 12 Dexterity saving throw when the reach the top next to the glossy floor or fall back into the pit, taking 2d6 falling damage if they are not secured by anything. The trap door over the pit can be disabled by wedging small, sturdy devices into it, such as pitons with a successful DC 14 Dexterity check. With thieves’ tools, this check has advantage.

 

Bubble Floor

 

The dirt floor is irregularly shaped and covered in small mounds.

Mechanical Trap

Several small mounds cover the floor. Each mound is filled with flammable gas. A DC 14 Wisdom (Perception) check detects the faint odor of gas. A DC 14 Nature or Survival check determines that the gas is flammable. The mounds can be avoided with a DC 12 Dexterity (Acrobatics) check each time a movement action is used. If it fails, then a mound is stepped upon and it releases the gas. The gas ignites if there is any open flame within 10′. If it ignites, it deals 3d6 fire damage to all creatures within 10′. A successful DC 14 Dexterity saving throw reduces this damage by half. The mounds can easily be bled of their stored gas and will not explode if there is no flame present. However, the mounds refill on their own in 1d12 + 12 hours.

 

Stuck Door

 

A wooden door is wedged into the door frame.

Mechanical Trap

The door is supporting the wall. The wall collapses if the door is removed. A DC 14 Intelligence (Investigation) check reveals that the frame around the door is resting its weight on the door. The door requires a DC 16 Strength check to force open, or can be destroyed. It has AC 15 and 27 hp. If the door is destroyed or forced open, the wall collapses. Creatures within 5 feet of the wall must succeed on a DC 14 Dexterity saving throw or take 2d6 bludgeoning damage. A DC 14 Intelligence (Investigation) check will allow the wall to be shored up with existing materials near by. Not only will this keep the wall from falling, it will also grant advantage on checks to force the door open.

 

Mesh Pit

 

A small wooden door leads into the side of the keep.

Mechanical Trap

The area immediately in front of the door has a trap door that covers a 60 foot deep pit. 10 feet down the pit, diamond studded fine wires have been strung in a mesh. Opening the door causes the trap door to open. The mechanism to open the pit is a small lever that is on the other side of the door. When the door opens, it pushes the lever. A DC 14 Wisdom (Perception) check reveals that a 10′ x 10′ area in front of the door is unusually level. Clearing the area reveals a split wooden door underneath. When the door is opened, the trap door opens up in the middle, Creatures on the 10′ x 10′ area in front of the door must make a DC 14 Dexterity saving throw or be dumped into the pit. Creatures falling into the pit take 6d6 falling damage, suffer a +4 melee attack for an additional 6d6 slashing damage. The trap is easily disabled from the other side of the door. From the outside, it requires a DC 16 Dexterity check with thieves’ tools to jam the supports under the door, keeping them from sliding back.