Which river is longer?
Two cards, one guess. Tap the one you think wins and the numbers roll out. Ten rounds, then a score to argue about. 90 rivers in the deck.
Which river is longer?
0/10
Shuffling the cards.
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ROUND 1/10 STREAK 0 BEST 0 RIVERS
Play another mode
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How it works
Every round deals two cards from the mode's deck. Tap the one you think wins, or press Left and Right, or 1 and 2. Both numbers roll out, the right card fills green, the wrong pick gets a line through it, and Enter deals the next pair. Ten rounds make a run.
Pairs are only dealt when the two values differ by at least 15 percent (12 years in history, 8 minutes for films), so rounding in the data can never make a round unfair. Nothing repeats inside a run.
Figures are rounded reference values, close enough to settle an argument, not a citation. Each mode names the vintage of its figures just under the cards.
Your best score in each mode is kept in this browser and nowhere else. The only thing this page reports is that a run finished and what it scored.