The buy-in for our three-day challenge was $1,000 of the USDC stablecoin. Each of us had to walk 10,000 steps a day; every day we miss that goal, we’ll surrender $333 to the prize pool. At the end of the challenge, those who meet the daily goal split that pool. We each have full control of our original deposits; as long as we walk 10,000 steps a day, we’ll get that money back.