There's a game for big bears and big bulls called «get your opponent to expire regular futures contracts. Index futures are settled and the winner takes an instant profit.

As you can see from the chart of the S&P 500 (expiration date is circled in red), the bulls were confidently winning until September 17, 2021, and each expiration point was higher than the previous one, but the bears never gave up and increased their bets. This is shown in the second chart, where we can see the growth of Open Interest.

The bears closed the last contract in their favor, winning the first victory of the year.