How to play

• Walk into a crate to push it; there is no way to pull one back.
• Only one crate can be pushed at a time, and never into a wall or another crate.
• Put every crate on a marked square to finish the level.
• Undo is unlimited — a mistake costs moves, not the level.
• Levels get larger and gain more crates as you go.

Tips

• A crate in a corner is lost for good; a crate against a wall can only slide along it.
• Plan the last crate first: decide which square each one is going to before you push anything.
• Clear the crates nearest the exit of the room last, or they will block your own path.
• When a level looks impossible, undo five moves instead of restarting — the mistake is usually recent.