3 Free RPG Traps | Clockwork Contraptions
By Sebastian Duesing
Hall of Venerable Warriors
Mechanical trap (Complex trap, level 5-10, setback)
Description. This long hall is lined with bronze statues that are fully articulated automata. The hall itself is at least 60 feet long and 15 feet wide. The statues are adorned in fancy armor and wield a vast array of bladed weapons. They all are bedecked in polished stones, gems, and pearls.
Trigger. Attempting to pry a precious stone from one of the automata triggers the trap.
Initiative. The trap acts on initiative count 20 and initiative count 10.
Active Elements. When the trap is triggered, the statues seemingly spring to life.
Weapon Strikes (Initiative 20). The automata attack each character in the hall with a +7 bonus to hit, dealing 7 (2d6) points of slashing damage on a success.
Flurry of Blades (Initiative 20). The statues fill an area of the hall with swirling swordplay. A section of the hall the size of a 15-foot cube becomes difficult terrain until the trap takes this action again. A character that moves in this area takes 5 (2d4) slashing damage for every 5 feet that they move.
Coordinated Attack (Initiative 10). A cluster of statues attempts to pummel a character who must make a DC 13 Strength saving throw. On a failed save, the character takes 22 (4d10) points of bludgeoning damage and is knocked prone. On a successful save, the character takes half damage and is not knocked prone.
Constant Elements. The movement of the statues produces horrifically loud clanging and grinding sounds. Characters in the area of the hall are deafened.
Countermeasures. A successful DC 18 Wisdom (Perception) check can detect wires, cogs, and pistons concealed within the joints of the statues, indicating that they are capable of motion. The trap can be disabled by disconnecting the wires of all the automata, which requires an hour of work and successful DC 14 Dexterity (Thieves’ Tools) check.
Damaging the statues can also impair the functioning of the trap. The trap is a Gargantuan object with 75 hit points, an AC of 18, and immunity to poison and psychic damage. When its hit points are reduced below 50, its attack bonus is reduced to +5, and the damage of the Coordinated Attack is reduced to 11 (2d10). When its hit points are reduced below 25, its attack bonus is reduced to +3, it can no longer use Flurry of Blades, and creatures in the area of the hall are no longer deafened.
Harrick’s Horrifying Cuckoo Clock
Mechanical trap (Simple trap, level 1-4, dangerous)
Description. This trap is concealed within a fortified door, safe, or vault. It consists of a well-concealed miniature trapdoor that can pop open to reveal a bird automaton like a cuckoo clock.
Trigger. Unsuccessfully attempting to pick the lock of the door, safe, or a vault in which this trap is concealed will trigger this trap.
Effect. When a character fails a check to pick the lock of the structure that contains this trap, the hidden trapdoor flies open. The spring-loaded cuckoo pops out, and the trap produces a cacophonous screeching sound, which can be heard from up to 300 feet away. The character that triggered the trap must succeed on a DC 13 Wisdom saving throw or be frightened until the end of their next turn. Additionally, all creatures within 30 feet that can hear the sound must make a DC 13 Constitution saving throw. A creature takes 7 (2d6) points of thunder damage on a failed saving throw, or half as much on a success. After the cuckoo screeches, it retracts back into the mechanism, and the trapdoor shuts, resetting the trap.
Countermeasures. The clockwork mechanism of this trap can be detected with a successful DC 15 Wisdom (Perception) check made to examine the structure that contains it. Once detected, the trap can be disabled with a successful DC 13 Dexterity (Thieves’ Tools) check. In addition, effects that suppress sound, like the silence spell, render the loud screech harmless.
The Ticking Time Bomb
Mechanical trap (Simple trap, level 11-16, deadly)
Description. There is a pressure plate set within the floor. Above it, a thin seam in the ceiling indicates the presence of a hidden trapdoor about 5 feet square.
Trigger. Stepping on the pressure plate triggers the trap. Tiny creatures are too lightweight to activate it.
Effect. When the trap is triggered, the trapdoor in the ceiling opens, and a heavy steel cage slams down on the area centered on the pressure plate. The character that stepped on the pressure plate must succeed on a DC 18 Dexterity saving throw or be trapped in the cage. The cage is 5 feet square and 10 feet high, and its walls are solid steel. On the cage is a clock face, and several wires and coils stretch from the clock to a device at the top of the cage. A creature within the cage has full cover.
The clock face counts down, starting the moment the cage reaches the ground. The game master should determine the time until the trap activates: it may be 30 seconds (5 rounds), one minute (10 rounds), or a different time of the game master's choice. After that time limit runs out, the device at the top activates and triggers an explosion within the cage, and any creature inside the cage must make a DC 18 Constitution saving throw, taking 88 (16d10) force damage on a failed saving throw, or half as much on a success.
Countermeasures. The pressure plate can be detected with a successful DC 18 Wisdom (Perception) check, and the seam around the edge of the trapdoor in the ceiling can be noticed with a successful DC 16 Wisdom (Perception) check. With a successful DC 20 Intelligence (Investigation) check, a character can discern the workings of the explosive mechanism and identify how to disable it. A successful DC 18 Dexterity (Thieves’ Tools) check can disable the explosive mechanism. Characters can also pry the cage up from the floor, potentially creating enough space for a trapped character to escape. Lifting the cage 2 feet off the floor requires a successful DC 20 Strength (Athletics) check.