A SMALL MAZE. A CHAIN REACTION.
Build a way through. Leave room for what follows.
All couriers must reach E from S. A completed route becomes an occupied trail, blocking every later courier. Only S and E can be shared.
Wall paints barriers; Erase removes walls, relays, and gates. Drag either tool. Entrance and Exit move S and E to empty floor. They cannot be erased.
Relay places a diamond station. Gate places a striped door. Choose channel A, B, or C. Each channel has at most one of each; placing it again moves it. Erase walls before placing objects.
Couriers take a shortest route, breaking ties east, south, west, then north. Each courier starts with no activated relays. Visiting a relay unlocks its matching gate for that courier only. Relays are optional unless a gate requires them.
A dotted line previews the plan. Trails form during movement and become barriers on arrival—including relay and gate cells. A courier may revisit its own cells while collecting relays.
Validate checks the first courier’s route. Run Relay tests the whole sequence. Stop returns to editing. Replaying starts with fresh trails. Undo and Redo also cover Clear and Load Example.
Keyboard: 1–6 selects tools; focus the grid and use arrow keys, then Space/Enter to edit. Ctrl/Cmd+Z undoes; Ctrl/Cmd+Shift+Z redoes. Escape closes this guide.
Your maze and settings save automatically in this browser. Restore last success loads the last build that completed every courier. Reduced motion shows each complete route without moving a bot. No data leaves this device.