The hand

The pack is dealt into two piles. You only see your top card. Choose a category. The higher number wins both cards, and they go to the bottom of the winner’s pile. The winner calls next.

A tie

If the numbers match, both cards go on the pot and the same player calls again from the next card. The next player to win a call takes the pot as well.

Born

Born is the year of birth. The later year wins, so 1977 beats 1643, and both beat any year BCE.

One best card in each category

• Lifespan: Leopold Vietoris, 110 years.
• Named ideas: Leonhard Euler, 16.
• Countries: Paul Erdős, 4.
• Students: David Hilbert, 79 doctoral students.
• Born: Maryam Mirzakhani, 1977.

Other cards can tie with each other. Only the top of each list is unique. Tap the i on a row to see the list behind a number. Ancient lifespans use the conventional dates from the MacTutor history of mathematics. Students are the Mathematics Genealogy Project count from October 2026.

Ways to play

• Computer. Easy calls almost at random. Medium plays the category where its card ranks highest in the pack. Hard remembers which cards you still hold, but not the order.
• Friend. Pass the device between calls so the other player does not see your next card.
• Online. Host a room, or join with a code. The server keeps the piles. You only receive your own top card.

Keys 1 to 5 choose a category on your turn. Settings can deal a quicker 20-card pack.