2024 is the 50th anniversary year of Dungeons & Dragons, so I'm running the game that gave me my first taste of role-playing games: Basic D&D, 1981, right out of the pink box.
A dungeon has been discovered beneath the keep's guild house. There's treasure in there! Also monsters and traps and who knows what else. You're a party of brand-new 1st level adventurers, and you're at the entrance to the dungeon. Good luck.
(You can bring along your own character if you like, or make one when you arrive!)
(I have some personal rules changes and additions, that's how you do it old school style. But they're pretty minor. Moldvay, Morgue's Way.)