Check out https://www.kiwico.com/standupmaths and get 50% off your first month of any subscription! Subscribe to Steve Mould’s channel. I sent him the next video challenge along with the Monomatch cards. null Support me on Patreon and get sent three "Monomatch Myriad" cards to check. https://www.patreon.com/posts/50645477/ Here is the bonus 'behind the cards' video on how I made Monomatch Myriad. https://www.youtube.com/watch?v=_l6h8v6R7yo It occurs to me it would be foolish to not provide Amazon referral links but don’t forget about your local independent toy retailers! USA SPOT IT: https://www.amazon.com/s?k=spot+it&ref=nb_sb_noss?_encoding=UTF8&tag=stanupmath-20 UK DOBBLE: https://www.amazon.co.uk/s?k=dobble&ref=sr_1_1?_encoding=UTF8&tag=stanupmath-21 This is the student video I mentioned: "How to make the card game Dobble (and the Maths behind it!)" https://www.youtube.com/watch?v=oyqD1Sg5M4Q Double Dobble https://aperiodical.com/2020/05/the-big-lock-down-math-off-match-22/ Droste Dobble http://christianp.github.io/droste-dobble/ https://mathsjam.com/assets/talks/2015/ChristianPerfect-DrosteDobble/#/ "A finite projective plane exists when the order n is a power of a prime." https://mathworld.wolfram.com/ProjectivePlane.html Finite projective plane of order 4 image from here: https://demonstrations.wolfram.com/ProjectivePlanesOfLowOrder/ Catch the match! https://boardgamegeek.com/boardgame/1321/catch-match/credits The American Mathematical Monthly Vol. 13, No. 11, Nov., 1906 https://www.jstor.org/stable/i349244 Vol. 14, No. 5, May, 1907 https://www.jstor.org/stable/i349250 CORRECTIONS - At 06:35 Dimitri Provoost spotted that some of the star and cross symbols on the diagonal red lines are accidentally swapped around. Good spot Dimitri! - I think once or twice I say "card" when I mean "symbol". I blame too much time spent with projective planes. - Let me know if you spot any other mistakes! Thanks to my Patreon supporters who keep me well-stocked with children's card games. And now 101 pentagons all featuring a happy little house. https://www.patreon.com/standupmaths Filming and grading by Alex Genn-Bash Editing by Matt Parker Graphics by Sam Hartburn and Matt Parker Music by Howard Carter Design by Simon Wright and Adam Robinson MATT PARKER: Stand-up Mathematician Website: http://standupmaths.com/ US book: https://www.penguinrandomhouse.com/books/610964/humble-pi-by-matt-parker/ UK book: https://mathsgear.co.uk/collections/books/products/humble-pi-signed-paperback