Cargo Call: Unblock Puzzle

A board packed with crates. Doors around the edge. And a manifest — a running order that names which crate leaves next, and which door it leaves by.

The job is not to clear what you can. It's to clear what's called.

Drag a crate and it slides until something stops it. The called crate is usually at the bottom of the heap with three others on top of it, and those have to go somewhere too. Finding the first move often means working four layers back: to shift this, move that; to shift that, move the other.

• 400 levels, every one of them played through. Each board was built offline and solved from end to end before it was chosen. You will never meet a board that cannot be finished — it is measured, not hoped for.

• 40 board shapes. Courtyards, aisles, bastions, necks, rings. What changes is not only where the doors are, but what is standing in front of them.

• Lashed and chained crates. A lashed crate never moves; it ships where it stands, when it's called. A chained pair can't stray far from each other — and the strap sags by exactly how much slack is left, so the rule tells you itself.

• A clock, but not an enemy. Every board's timer comes from measuring its own solution. The difficulty is in the board, not the stopwatch.

• Nothing you need is for sale. Undo a move, take a hint, defer the current call, open an extra bay — all paid for with coins you earn by playing. Watch a short video for coins if you want them; if you never ask, you never see one. Time and second chances are not sold: the clock is pressure, not a shop.

There is a single one-off purchase to remove the adverts. Nothing else changes.