Counterweight
Courier
Two lifts. One rope. No motor.
The heavier side goes down and pulls the lighter side up. Your parcels are also your power supply.
Shelf → load. Lift → unload. Two items per lift.
A · west liftB · east lift
Read the board as text
Floors run from 0 (ground) to 4 (roof). Shelves stay on their own side; the two lift floors always add up to 4.| Floor | A · west | B · east |
|---|
All parcels delivered. Gravity sends its regards.
How the machinery works
Click a parcel on a shelf to load it into the adjacent lift. Click a parcel in a lift to unload it onto that floor’s shelf. Only parcels beside a lift can be loaded. Each lift holds two items; the numbers are their weights, not their sizes.
Release brake moves both lifts exactly one floor. Equal loads stay still. Shelves on opposite sides do not connect. Delivery counts only when a parcel is unloaded at its marked address. Stones and iron have no destination. Delivered parcels can be picked up again.
Undo is unlimited. There is no timer, no penalty, and no automatic motion. The action count is there for comparing plans, not grading them. This is a discrete puzzle model, not a machinery simulator.
Workshop: an extra job that did not make the cut
I tested a five-cargo situation where the shortest route leaves iron on a middle shelf and collects it on the return journey. That plan takes 21 actions. But a second search, forbidding that kind of advance placement, still finishes in 23. The apparent new puzzle was an optional shortcut through another long delivery detour.
It has not earned a sixth job. This is a mechanical comparison, not a playtest or proof that staging cannot work. A second candidate put three east-side deliveries into a two-slot lift. The middle-floor pickup really is blocked by a full car, but delivering one parcel first frees the slot. Both the unrestricted solution and a search forbidding off-destination cargo storage finish in 18 actions. The browser confirms the obstruction, a balanced swap, and the delivery-first escape.