I think you are teetering on the edge of the rabbit hole of a domain specific language for the representation of board game rules. Unless you want to write a new emulator for each new multiplayer game, that's the hole you'll dive down. But once down there, you'll realize you're basically making a programming language with a board game theme, as any language sophisticated enough to represent most board games is destined to become a Turing tarpit. At that point the project has become self defeating, as you are now coding each new game in a programming language you invented to avoid coding each new game.