Ferry the cargo across the river without leaving the wrong pair alone, while the tide changes your boat each trip.
You must move a set of cargo items across a river by boat. Certain pairs must never be left together on a bank without you there to watch them. The twist: the tide changes the boat's capacity on every crossing, so how many items you can carry shifts each trip and the order of your moves becomes the whole puzzle. Get everything across safely in as few crossings as possible.
River Reckoning reimagines the classic river-crossing puzzle with a tide-driven twist, training constraint-based planning.
Ferrying items across a river where certain pairs cannot be left alone is the river crossing puzzle, and its most famous instance — the wolf, goat and cabbage — appears in a manuscript attributed to Alcuin of York around the year 800.
The original element is the tide: the boat's capacity changes on every crossing, so how much you can carry depends on when you go.
The classic puzzle is a fixed search problem with one famous trick — you have to bring something back. A capacity that shifts each trip turns it into scheduling, because the same set of moves succeeds or fails depending on the order you attempt it in.
Further reading: Ferry the Cargo Across
River Reckoning is an original, free browser game that reimagines the classic river-crossing puzzle with a tide-driven capacity twist. It is built in-house and plays in your browser.
Every crossing is a decision, every decision a balance between forward motion and the safety of what you leave behind.