Fusillade of Drow Poison Darts

Mechanical trap
A Fusillade of Drow Poison Darts turns an ordinary doorway into a dangerous ambush. Tiny holes concealed beneath dust and cobwebs line the walls, ready to launch poisoned darts when a creature steps on a hidden pressure plate.
Detecting the Trap. A character who succeeds on a DC 15 Wisdom (Perception) check notices the holes in the walls. A character who succeeds on a DC 15 Intelligence (Investigation) check identifies the pressure plate in the doorway’s threshold by recognizing differences between its mortar and stonework and the surrounding floor.
Disabling the Trap. Wedging an iron spike or another suitable object beneath the pressure plate prevents it from activating. Blocking the dart holes with cloth or wax prevents the darts from launching.
Trigger. The trap activates when more than 20 pounds of weight is placed on the pressure plate, releasing four darts.
Effect. Each dart makes a ranged attack with a +8 bonus against a randomly determined target within 10 feet of the pressure plate. A target hit by a dart takes 2 (1d4) piercing damage and must make a DC 13 Constitution saving throw against Drow Poison.
On a failed save, the target has the Poisoned condition for 1 hour. If the saving throw fails by 5 or more, the target also has the Unconscious condition while Poisoned in this way. The target wakes up if it takes damage or another creature uses an action to shake it awake. Waking up does not end the Poisoned condition.