21

21 turns the whole table into one running headcount. Starting with the thrower and moving clockwise, each person calls out the next one, two or three numbers in the sequence — one, then two-three, then four, and so on. Nobody's just taking a turn: everyone's doing the same sum in their head, watching the target creep closer. Whoever's go lands on twenty-one finishes their drink there and then.

At a real table it starts as a giggling formality and turns serious somewhere around fifteen. People start counting on fingers under the table, muttering the running total to themselves, and someone always throws in a wobbly "seventeen... eighteen, nineteen" that gets immediately disputed. The last few numbers get slow and cagey, because everyone's worked out they can steer exactly who's left holding twenty-one.

That's the whole game really: you choose how many numbers to say each go, so you can nudge the danger onto whoever's next. Say one number and pass it straight to your neighbour; say three and you might skip past the number altogether. The only real etiquette is doing your maths quietly — muttering your plan out loud before your turn gets you dirty looks and, fairly often, a recount.

It sits in the 2nd Circle, one of the board's bigger rings, so it comes round often enough that regulars start eyeing the danger zone the second the dart's still wobbling in the wedge.