The Grand Design

Every component comes from the Mechanic and they combine at a Tinkerer's Workshop, so the earliest you can hold one is shortly after Skeletron dies and she is out of her cell. It absorbs the viewing lens, the measuring ruler, the multicolor wrench and the cutter, and on top of that it handles Actuators, which the wrench on its own will not touch. Freeing four hotbar slots is the small win. The reason to build it is everything below.

Pressing the interact key opens a small menu at your cursor with a button for each wire color, one for actuators, and one that flips the whole tool between placing and pulling up. You can have any combination of colors armed at once, so it will lay four colors in a single pass or strip all four out of a wall in one drag. When the menu is closed a row of small colored squares sits beside the cursor showing what is armed and which direction you are working in, which is worth glancing at before you start a long run in harvest mode by mistake.

Instead of tapping one tile at a time, you hold the button and drag out a path, and that path is allowed exactly one corner. Which way the corner bends is decided by which way your character is facing, so if the route is turning on the wrong side, turn around before you let go. You can run, fly or ride while the line is still being drawn, so laying a long connection across the sky on a mount takes one held button rather than a thousand clicks. Two limits: it places roughly a thousand tiles per release, and holding the button for about a minute without releasing cancels the whole draw.

It works anywhere on screen, ignoring the block reach that constrains every wrench. That is what makes long teleporter runs and roof wiring bearable, and it is also the safest way to disarm a trap: you can cut the wire on a boulder or an explosive from across the room without ever entering its trigger area. Anything you pull up lands directly at your feet regardless of distance or walls in the way, so there is no return trip to pick up your wire.

The one hazard is that the collection point is you. Cut wire while you are standing in lava, with whatever is keeping you alive in there, and it drops into the lava and burns.

Keeping it anywhere in your inventory, held or not, gives you a set of visibility switches. Each wire color and the actuators can be shown at full brightness, left to normal lighting, or dimmed to a faint overlay. There is also a switch for whether wiring is drawn all the time or only while a mechanism item is in your hand.

This is more useful than it sounds when you are untangling something already built. Fade the colors you are not working on, force the one you are to full brightness, and a dungeon trap network or a factory floor stops being a mess of overlapping lines.

Smart cursor does not work with it. The naturally generated dungeon traps are wired diagonally, and picking those apart by hand is genuinely faster with a plain Wire Cutter. Keep one in a chest rather than melting everything down.

The internal name for the item and its projectile is a pun on kites, which is roughly what the inventory sprite looks like if you squint. The sprite itself is a blueprint, and the name is probably a nod to the Stephen Hawking book.