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21x Card Game Preview

This is a preview copy provided for free by the publisher. It does not represent the final published copy. The game is being crowd funded soon. For more information, read here.


21X is from Naylor Games, the team behind the brilliant Magnate: The First City. It's a bit of a change for the team behind the huge box experience of Magnate. Going from a sea of plastic to a simple deck of cards.


Publisher James Naylor said, "It’s very different to our other titles. It’s a super quick, maths puzzle game you can play with anyone from children to university maths professors."


Well, lets take a look ourselves and see how it plays.

In 21X players are trying to get there cards to add up to 21. The game plays just like Blackjack, but the cards are very different!


Set Up


The first thing to do is decide your desired difficulty. The cards are all marked in the top right and bottom left corner with either a Triangle, a Triangle and a Square, or both of these and a Pentagon. Level one with just the triangle has simpler easier equations with whole number cards with addition, subtraction, and multiplication. Level two has more complex equations with divisions, brackets, indices, and powers. Level three brings in negative numbers in divisions and even more difficult equations.


Take out any cards you don't want to use and then shuffle the deck and deal each player two cards, just like normal Blackjack. Place the remaining deck face down between the players along with the player aids. You are now ready to play.


How to Play


All players simultaneously reveal their cards and the round begins. Each player will now try to work out a value for X that makes their cards add up to 21, or as close as possible without going bust. This means by scoring over 21. The value of N is determined by the number of cards they have in their hand. So will change if they get more cards. X can be whatever they want but must be the same across all cards if they have more than one X present across multiple cards. X can be positive or negative but must be a whole number and cannot be zero.

Any players may decide to twist in order to draw another card. You can do this up to three times for a maximum of five cards. If you cannot get to 21 exactly you can stick by calling out the number they can get to. After which time, all other players now have a maximum of one minute to carry on playing, trying to get closer to 21 than the player who just stuck.


Once you stick, you cannot change your number. You cannot stick on 20. And once one player sticks, no other player can now also stick. The first player to make 21 correctly wins. If no one makes 21, the player who can make the number closest to 21 without going over is the winner. The winner must always show their solution. If they have got their math wrong, the winner is the person with the next highest value and so on. You can play multiple times, in a race to three, five etc, or however you see fit.

Publisher, James Naylor said, "I have high hopes there’s an educational angle here as well as being a great stocking-filler gift for the mathy friend in your life. The teach takes less than 1 minute and it being just a single deck of cards, you can take it anywhere. It takes less than 5 minutes to play. It has adjustable difficulty too, so you can tailor it really well to group." James continues, "I personally love it and felt compelled to sign-it the moment the designer Leo Samson first played it with me. It’s just one of those things that felt like it should exist already. If you like math puzzles or mental arithmetic, I think you’ll really like it. If not… it’s almost certainly not for you."

Is it Fun


Some of the cards blow my mind, I am certainly not a mathematician. However, I have loved playing with my son (nine). He loved the concept and trying to work out the best way to get as close to 21 as possible. Which he did, quite often! More than me. Some cards are pretty simple. Just a flat number, or negative five for example. Others are more complex and require a lot more thought.


The N concept was very clever. As this changes when you get more cards. You could get to within one or two of 21 with the cards you have. And then twist to try and get to 21 exactly but of course, any N card you had is now a different value.


Getting to 21 is very satisfying. If you like working out math problems then you will love this. If not, I would still consider it to try with your friends and family who do. I have introduced this to a few (very clever) non-gamers who were blown away by it and are now looking at what other modern games may be for them. It certainly is unique in that aspect. I don't see many other games brining in scientists and mathematicians to the hobby as much as this!

For more information, head here.

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