Tavern games that people gather around. These are physical objects in the world, not menus — players walk up, sit down at a real table, wager real money and play with their hands while anyone nearby can stop and watch the match.
Custom 3D props, native RDR2 audio and cinematic cameras, with state that survives a server restart: a game cut short by a reboot resumes on the same board, with the same pot.