The cave scanner functions much like a laser 3D scanner. It sends pulses into the ground and can detect the interface between air and other blocks, which it will render in the world. This allows you to map caves from the surface. Its field of view is 16 blocks by default, and can be moved around by right-clicking the block. Right-click will push it in the direction you are looking, and shift-right-clicking will push it in the opposite direction you are looking. Caves are color coded based on depth.
Required Power: 262144W
Move the selected region by right-clicking the block
Power Input: Any side