Jacob’s Ladder

 

A ladder crosses the chasm at about a 45 degree incline.

Mechanical Trap

The ladder is balanced on a single pole at the top and bottom but secured at the ends at the top with detachable clamps. A DC 12 Wisdom (Perception) check detects the the small cylinder at the end that is closest allows for the ladder to rotate. The clamps at the top support 100lb. of weight. When a creature that weighs more then 100 lbs. climbs the ladder, the clamps at the top snap after the creature has climbed 1d4 rungs. This causes the ladder to unbalance. The creature on the ladder must make a DC 16 Dexterity saving throw to keep the ladder balanced. On a failure, the ladder flips over and the creature falls, taking 6d6 damage. On a success, the creature is still on the ladder. To climb each rung, the creature must make a DC 14 Dexterity (Acrobatics) check. There are 10 total rungs on the ladder. The ladder can be secured by disabling the rotation on the bottom rung. This is achieved by successfully making a DC 14 Dexterity check with thieves’ tools.

 

Double Paned Glass

 

A thick window looks into what looks to be a library or study. The door is on the opposite side of the room.

Mechanical Trap

The window is double paned. The interior is filled with acid. A DC 14 Wisdom (Perception) check shows a small line near the top of the window. On closer inspection, this line turns out to be the top of the fluid in the window. If the window is broken, the acid spills out onto the floor. All creatures within a 10′ radius of the take 4d4 acid damage, and then continue to take 1d4 acid damage for an additional 1d4 rounds. A successful DC 14 Dexterity saving throw reduces the initial damage in half and negates the ongoing damage. The trap can be disabled by drilling a small hole in the glass and letting the acid slowly leak out. This requires a successful DC 14 Dexterity check with thieves’ tools. Failure means the glass shatters and breaks.

 

Chandelier

 

A chandelier hangs above a door. A rope runs from the chandelier and is tied to the door handle.

Mechanical Trap

The chandelier falls when it is untied. The chandelier is heavy enough that the door cannot be opened until the rope is removed. A DC 12 Wisdom (Perception) shows that the chandelier’s crystals are filled with a clear liquid. When the rope is untied or cut, it requires a DC 20 Strength check to prevent the chandelier from falling to the ground. If the chandelier falls, any creatures directly underneath the 5 foot square must make a DC 14 Dexterity saving throw or take 3d6 bludgeoning damage. Additionally, the crystals break, and the liquid bursts into flames. All creatures within 30′ take 4d6 fire damage, or half damage on a successful DC 14 Dexterity saving throw. If the crystals are removed, or the chandelier extinguished, the fire will not start.

 

Anti Climber Tower

 

The top of the tower is just a wooden platform of planks. The planks extend out into space over the tower’s walls by 2 feet.

Mechanical Trap

The planks are on a fulcrum on the tower’s walls. A DC 14 Wisdom (Perception) check detects that the inside end of the outer planks are all slightly uneven, with some raised a little more than others. When a creature applies weight to the outer 2 feet of the plank, without any counter weight on the other side, it rotates downwards towards the ground. The creature applying the weight must make a DC 14 Dexterity saving throw of fall towards the ground, taking 3d6 damage. The planks can be disabled with a DC 10 Dexterity check by securing them to the rest of the platform. Or they can have a counterweight equal to 1/2 or more of any weight applied to the far end.

 

Lead Ball

 

A ventilation hole for a fire is right next to the door.

Mechanical Trap

The ventilation hole contains a heavy lead ball held in place by a metal sheet. A pressure plate on the floor retracts the sheet, dropping the ball. A DC 12 Wisdom (Perception) check detects the faint outline of a square in front of the door. Stepping on the plate drops the ball. The creature must make a DC 12 Dexterity saving throw or take 2d6 bludgeoning damage. The pressure plate can be disabled with a DC 12 Dexterity check with thieves’ tools. If tools are not used, the check has disadvantage. The pressure plate can also be avoided by opening the door and stepping over it. This requires a DC 10 Dexterity (Acrobatics) check to open the door and a DC 5 Dexterity (Acrobatics) check to step over the plate.

 

Oil on the Stove

 

The smell of cooking oil permeates the air.

Mechanical Trap

A hot pot of cooking oil is on the oven. The exit door causes a water bucket in the vent above the stove to dump water into the oil. A DC 12 Wisdom (Perception) check will reveal that the top of the door has twine attached to it that runs along the seam between the ceiling and wall and enters the vent. When the door is opened, the water spills into the pot. Every creature in the room takes 3d6 fire damage and is on fire for 1d4 rounds. While on fire, a creature takes 1d4 fire damage at the start of their turn. A DC 14 Dexterity saving throw halves the damage, and also means that the creature is not on fire and does not take the ongoing fire damage. The trap can be disabled simply by cutting the twine before opening the door.

 

Crawlspace

 

A small wooden crawlspace can be entered at the back of the room.

Mechanical Trap

The crawlspace is lined with wooden planks, all of which have a little give. This give causes some of the nails to pop out slightly while using it. A DC 14 Intelligence (Investigation) check reveals that the crawlspace is old and needs repair. The boards are somewhat loose and it looks like not all of the nails are secured. Each time a creature makes a move in the crawlspace, they must make a DC 14 Dexterity (Acrobatics) check, or get caught on a nail, taking 1 point of damage. If the creature is wearing armor, and fails the check by 5 or more, the creature also becomes restrained, and movement ends. It requires an action by the creature or another creature to end the restrained effect. If the creature moves at half speed, the creature will gain advantage on the check while moving.

 

Piston Tiles

 

The stone tiles in this room are all a uniform 5 foot square.

Mechanical Trap

Each tile in the middle of the room has a pit and piston underneath it. First it drops, igniting the tunnel, and then slams up to the ceiling. A DC 14 Wisdom (Perception) check reveals that the tiles 10′ into the room have a couple of mm of space between it and the next tile. This area is as wide as the room and 20 ft deep. When one of these tiles is stepped on, the tile immediately drops 20 feet. A creature on the tile must make a DC 14 Dexterity saving throw or take 1d6 falling damage. When the piston hits the bottom, the pit fills with flame as an explosion drives the piston up again. Creatures in the pit take 3d6 fire damage, with a DC 16 Dexterity saving throw for half damage. The piston drives all the way to the ceiling. Creatures on the piston may make a DC 14 Dexterity saving throw when it leaves the pit to jump off. Otherwise, the creature takes 3d6 bludgeoning damage when the piston reaches the top. The piston then resets. Note that if a creature jumps to an adjacent tile that has a piston, this cycle is repeated. The trap can only be disabled from underneath the tile. A creature must get under the tile, requiring a DC 14 Acrobatics check to get under the tile while it is rising. The creature still takes 2d6 falling damage unless mitigated somehow. If the creature moves at any rate slower than normal falling speed, they will take 2d6 bludgeoning damage as the piston lands on top of them at the bottom, as there is only 3′ of clearance. Once underneath, a DC 16 Dexterity check with thieves’ tools will cause the piston to rise where it can be stopped and locked at any point. Creatures may also try to hop from one tile to another by making successive Dexterity saving throws from tile to tile. Once a creature is aware of the trap, these saving throws have advantage.

 

Breaking Windows

 

A few windows on the front of the building lead into an office.

Mechanical Trap

The windows are trapped from the inside. If they are opened, small hammers break the glass, sending shards outwards. A DC 10 Wisdom (Perception) check reveals the the inside of the window frames are lined with several small hammers on springs. If the window is opened, all of the spring loaded hammers fire, sending glass shards outwards. All creatures within 5′ of the window take 2d6 slashing damage, with a successful DC 12 Dexterity saving throw halving this damage. The trap can be easily disarmed from inside, by locating a small switch on each window with a DC 10 Wisdom (Perception) check and flipping it. The only way to disarm the windows from the outside is to break the glass. At this point, the hammers can be disarmed, or if they do fire, there is nothing for them to hit.

 

Glass Floor

 

A ornate stone floor spans the room.

Mechanical Trap

The floor is made of glass and been cleverly painted to look like stone. Underneath is a deep, spiked pit. A DC 10 Wisdom (Perception) check reveals that that floor does not feel like stone when stepped on, as it slightly flexes. If investigated, it is immediately obvious that the floor is made of glass. Creatures that move more than half speed, or take combat actions on the glass run the risk of the glass breaking. In order to not break the glass, a creature must make a DC 12 Dexterity (Acrobatics) check to avoid breaking the glass. If the creature is not aware that they are on glass, this check is at disadvantage. If the glass breaks, it creates a jagged 5′ diameter hole centered on the creature. All creatures within the diameter must make a DC 12 Dexterity saving throw or fall into the pit, taking 3d6 falling and 2d6 piercing damage. Those creatures that make their saving throw that are more than 5′ away from an exit to the room, must make the DC 12 Dexterity (Acrobatics) check to avoid breaking the glass again. This can cascade many times until the floor is entirely gone.