Actuator

The Actuator is a mechanism item sold by the Mechanic for 10 silver coins each. When activated, the tile it sits on toggles between active and inactive state, effectively allowing any block be toggled in this way like Active Stone Blocks.

Like Wire, Actuators are normally invisible and only become visible when a mechanism item is selected and are removed with the Wire Cutter.

Using Actuators in place of doors creates Blood Moon proof entrances, as well as doors your NPCs won't wander through.