Mitsuhama, a.k.a. 三津浜, is a game of buying and selling fish based upon the traditions in the port city of Mitsuhama. In the game, players are buying fish at auction, storing them in their warehouses, and then selling them to local restaurants.
On each turn, one player rolls four dice, corresponding to the four types of fish in the game, and places some or all of these up for auction. In real-time, the other players bid an amount of money they would pay for these fish. The auctioneer can choose to accept the highest bid or pay that bid themselves. Money from the auction is paid to either the auctioneer or the highest bidder, and can be paid by fixed value money cards, bartered with fish, or both. If the money card(s) paid from one player to another player are larger than the bid, no change is provided.
In each game, five restaurants are available for selling fish to. These are double sided and chosen randomly each game. Any players who gained fish from an auction in a turn are able to sell fish to the restaurants. Each player has a number of "employee cubes" used to track the amount of each type of fish in their warehouses, and when selling to a restaurant, one of these employees is removed from the warehouse and used to mark the income the player will receive from the restaurant at the end of the game.
The game will end when a predetermined number of employee cubes have been placed on a restaurant. The player with the most money wins, and this is a combination of the money cards in hand, fish remaining in warehouses, and income received from the restaurants.
The designer's family lives in Matsuyama, a city with some ports including Mitsuhama, and the painting on the cover of the box is one of the port made by his grandfather.