>>741635825 cards with random generic words on them. Ambiguity on what they could mean is important.
Split into two teams. Each team has a spymaster. The spymasters can see what colours each word are, the others (and us as the audience) cannot.
Taking it in turn, the spymaster comes up with a hint that must be in the form of one word and a number. The word should link to words of their team's colour, and the number is how many cards are being hinted at.
Rest of team discuss what words they think the clue relates to, eventually choosing a word. If it's the right colour, great, keep on going (within reason). If it's the other team's colour or neutral, the turn ends immediately. If it's the one black card (the assassin), the team loses and the game ends right then and there.
Other than the assassin clause, the winner is the team that finds all of their coloured cards first.
There's more in the finer details about what you're allowed to hint and how to guess, but that'll do as an overview.
The basic intrigue of the game comes from how vague the cards are and how limited the spymaster's communication is. It's very hard to clearly indicate specific cards without potentially hinting at others, and different people interpret clues in different ways.
