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Lock Trap

th tier (
(less than 1 hour)

A sturdy metal door features a boxy lock studded with sharp rivets. (Note: The lock may be on a chest instead, in which case the chest contains a Minor Treasure.)

Attempting to pick the lock with thieves’ tools triggers Critical Failure. Any other method of opening the lock results in a Success. (As is the case with most locks, there is a decent chance the key is somewhere nearby!)

Exploration. An Engineering or Investigation check reveals that the keyhole is large enough to contain a trap. A Perception check or an examination of the floor reveals a drop of dried blood on the floor near the lock.

Lock. A creature can make an Investigation or thieves’ tools check to probe the lock for traps. This check is made with advantage . On a success, the creature identifies the trap and makes Dexterity checks to disable the trap with advantage. Failing the check triggers a Critical Failure.

The lock can be smashed with a DC 19 Strength check or by attacking it (AC 19, 20 hit points, immunity to poison and psychic damage).

Protection. A character wearing gauntlets is immune to the trap’s damage but has disadvantage on Dexterity checks to pick the lock.

Spell Solve. Knock   unlocks the door but does not disable the trap.

Possible Solutions
  • A creature can make a thieves’ tools check to disable the trap.

Potential Outcomes

Critical Failure. A blade extends from the lock, jabbing at the fingers of a would-be lockpicker. The triggering creature takes 5 (2d4) slashing damage. A creature damaged by the blade has disadvantage on Dexterity checks involving manual dexterity (such as disarming traps) until it regains at least 1 hit point.

Failure. As a Critical Failure, except the blade deals 2 (1d4) slashing damage.

Success. The trap is disabled.

Critical Success. The trap is disabled, and the door is unlocked.