Dart Trap

The Dart Trap is a naturally occurring block that can be triggered by mechanical means.

They are sparsely located around the Cavern level and the entrance of the dungeon. Each one is spawned with a corresponding pressure plate wired to it.

Upon being triggered by a player or mob it will fire a poison dart. After this it has three second cooldown and then will fire again if still activated.

Setting up Dart Traps
A trigger can not simply be set adjacent to the desired object to be activated. They must be connected with wires. Because there is no way to craft wire or related tools, you need to have defeated Skeletron and freed the Mechanic NPC from the dungeon in order to set up your own Dart Traps.

Unlike Explosives, Dart Traps are blocks and can be placed on top of each other, so dart-firing walls can be created. Like most asymmetric furniture, they will be placed facing the direction the player is facing.

With some planning, Dart Traps can also be used to very quickly harvest an entire Mushroom/Glowing Mushroom/Vile Mushroom/Underground Jungle farms.

Mitigating Dart Traps

 * The darts fly fairly slowly and at range you can jump over them.
 * Enemies in the area of a Dart Trap will often wander onto the Pressure Plate and set it off.
 * By holding a wiring-related item such as an already-mined Dart Trap or a Wrench, any wire on screen will be highlighted in red, including the naturally spawned wires connecting a Dart Trap to its Pressure Plate.

Trivia

 * The dart trap's graphic resembles a stylized stone head. Traps involving such heads firing darts out of their mouths are a common sight in popular culture.