Imagine a cardanic hinge – the axis is upright and after going through a wooden floor that turns out to be the body of a ship, that axis ends up being the mast of said ship. Three spreaders rotate around it to provide balancing space for sailors, mice, bottles, crates. The spreaders are numbered (left or right to the mast, from five to ten), and the upper deck is divided into four quarters numbered 1-4. That’s the set-up for Riff Raff.
Each player has the same set of “stuff” and a hand of cards numbered 1-10. Choose one card, then reveal it simultaneously with the other players. Then place anything you want onto the numbered space you chose. If the players all go to one side, the whole ship will tumble in rather unforeseeable ways to and fro, with one or more items falling off the ship with players trying to catch them quickly. Whatever you catch, goes out of the game. What falls down counts to the things you try to put on the ship. The player getting rid first of all his things, is winning the game.