{"id":89002,"date":"2026-02-06T14:00:05","date_gmt":"2026-02-06T14:00:05","guid":{"rendered":"https:\/\/bigbossbattle.com\/?p=89002"},"modified":"2025-12-30T09:22:40","modified_gmt":"2025-12-30T09:22:40","slug":"21x-review","status":"publish","type":"post","link":"https:\/\/bigbossbattle.com\/21x-review\/","title":{"rendered":"21X is like playing Dr Kawashima\u2019s Brain Training, only you can\u2019t play it on the toilet."},"content":{"rendered":"<h5><strong><i>21X<\/i> comes to us from designer Leo Samson and published by Naylor Games, who gave us <i>Sub Terra<\/i> and <i>Snowdonia: Grand Tour<\/i>. Now comes their newest project to grant new life to the classic game of blackjack.\u00a0<\/strong><\/h5>\n<p><span style=\"font-weight: 400;\">Like <\/span><i><span style=\"font-weight: 400;\">blackjack<\/span><\/i><span style=\"font-weight: 400;\">, the goal of the game\u00a0 \u00a0 <span style=\"text-transform: initial;\">is to get a card total of 21, or as close as you can without going over. This new take is that each card, instead of just being a number, contains an algebraic expression. <\/span><\/span><span style=\"text-transform: initial;\">For those of you still here after reading \u201calgebraic expression\u201d this could be the game for you. You get dealt two cards and all players flip their cards at the same time. Your card may just be a number, but most cards contain an algebraic expression such as NX, 2-2X or 2X-10. Just to check again, still here? As that is literally how I, and several of my group felt at this point, but we soldiered on FOR SCIENCE!\u00a0<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-89003\" style=\"text-transform: initial;\" src=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-1024x768.jpg\" alt=\"\" width=\"606\" height=\"455\" srcset=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-1024x768.jpg 1024w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-300x225.jpg 300w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-150x113.jpg 150w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-768x576.jpg 768w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-1536x1152.jpg 1536w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-86x64.jpg 86w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x-600x450.jpg 600w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230344\/21x.jpg 1920w\" sizes=\"auto, (max-width: 606px) 100vw, 606px\" \/><\/p>\n<p><span style=\"font-weight: 400;\">In the game, N is the number of cards that you have in front of you, and X is always whatever number you want. But, the value of X must be the same on all cards. So if I receive 1-X and 2-2X, if I say that X is worth 3 or 4 or 10000, etc. it will simply not get me close enough to 21. But you can say that X is worth -6 so you get (1 &#8211; -6)+(2-2x-6)=21.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If you cannot get close to 21 (or close enough) with the cards that you have, you can draw additional cards up to a limit of five. However, once you draw a card, there is no way to discard it. Once a player states that they have 21, all players must stop, the result is checked and if they have, the game is over. If a player states \u201cstand\u201d, players start a one minute timer, you state your final total and what your X value is. The other players have that one minute to try and get closer to 21. After one minute, if they cannot, then the game is over, and closest to 21 wins.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncentre wp-image-89006\" style=\"text-transform: initial;\" src=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230404\/21x4-768x1024.jpg\" alt=\"\" width=\"489\" height=\"652\" srcset=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230404\/21x4-768x1024.jpg 768w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230404\/21x4-225x300.jpg 225w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230404\/21x4-113x150.jpg 113w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230404\/21x4-1152x1536.jpg 1152w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230404\/21x4-600x800.jpg 600w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230404\/21x4.jpg 1440w\" sizes=\"auto, (max-width: 489px) 100vw, 489px\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The gorgeous game box states that gameplay is between two to fifteen minutes, and I would say that is accurate. Within the box, there are enough cards for three decks, and they are split into three levels of complexity. Level one contains integers with simple expressions. Negative numbers. Addition, subtraction and multiplication. Level 2 brings in division by 2, brackets, indices\/powers. Finally Level 3 cards bring more complex divisions.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">There are also \u2018celebrity\u2019 cards which have famous number sequences, irrational numbers, factors, primes, from such household names as James Grime PhD, Kalie Steckles PhD and Matt Parker no PhD. The celebrity cards are beautiful cards with gold text, but unless you yourself are studying maths or physics at an advanced level, i think they will be as fun to play as when someone adds picture cards to Cards Against Humanity.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-89010\" style=\"text-transform: initial;\" src=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7-1024x387.jpg\" alt=\"\" width=\"1024\" height=\"387\" srcset=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7-1024x387.jpg 1024w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7-300x113.jpg 300w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7-150x57.jpg 150w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7-768x290.jpg 768w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7-1536x580.jpg 1536w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7-600x227.jpg 600w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27231448\/21x7.jpg 1920w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/p>\n<p><span style=\"font-weight: 400;\">I have very strange feelings about this game. If someone asked me, or at least asked me to write about whether I enjoyed this game, would I say that I had? In all honesty, no. I was lucky enough to play with some very intelligent scientists, but all of us were quickly intimidated by the difficulty of the equations, and all of us haven\u2019t had to do that level of maths for over a decade. We did enjoy the first hand, but after that, it just felt like we were doing homework.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">All g<\/span><span style=\"font-weight: 400;\">ames have a place, all games are a labour of love for someone and so they want others to get enjoyment from as well (except <\/span><i style=\"text-transform: initial;\">Catan<\/i><span style=\"font-weight: 400;\">, that wants to make you hate your friends). I do not feel that <\/span><i style=\"text-transform: initial;\">21X<\/i><span style=\"font-weight: 400;\"> is best played as a game.\u00a0<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncentre wp-image-89005\" style=\"text-transform: initial;\" src=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-1024x768.jpg\" alt=\"\" width=\"636\" height=\"477\" srcset=\"https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-1024x768.jpg 1024w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-300x225.jpg 300w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-150x113.jpg 150w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-768x576.jpg 768w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-1536x1152.jpg 1536w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-86x64.jpg 86w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3-600x450.jpg 600w, https:\/\/s3-b3bucket.s3.eu-west-2.amazonaws.com\/wp-content\/uploads\/2025\/11\/27230357\/21x3.jpg 1920w\" sizes=\"auto, (max-width: 636px) 100vw, 636px\" \/><\/p>\n<p><span style=\"font-weight: 400;\">If I have to race against another player to get to a total first, I just won\u2019t enjoy that. If I approach this game as a puzzle, where I pull the cards and I can take my time to find the best answer, that suddenly appeals to me a whole lot more. If you have someone in your life who is studying more complicated mathematics than basic arithmetic, then this would be a perfect game to sit down with them, and use it as a learning tool. Work through the problems together (or competitively) and a few hands a night might do wonders for their next exam or test.<\/span><\/p>\n<p><em>21X is available now <a href=\"https:\/\/www.board-game.co.uk\/product\/21x-limited-edition\/\">from Zatu Games<\/a>.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>21X comes to us from designer Leo Samson and published by Naylor Games, who gave us Sub Terra and Snowdonia: Grand Tour. Now comes their newest project to grant new life to the classic game of blackjack.\u00a0 Like blackjack, the goal of the game\u00a0 \u00a0 is to get a card total of 21, or as [&hellip;]<\/p>\n","protected":false},"author":124,"featured_media":89004,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2981],"tags":[11320,11322,11078],"class_list":["post-89002","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tabletop-reviews","tag-21x","tag-leo-samson","tag-naylor-games"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>21X is like playing Dr Kawashima\u2019s Brain Training, only you can\u2019t play it on the toilet. &#8211; Big Boss Battle (B3)<\/title>\n<meta name=\"description\" content=\"Dive into the world of 21X, a unique card game combining a mix of algebraic expressions with traditional gameplay.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.bigbossbattle.com\/21x-review\/\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"21X is like playing Dr Kawashima\u2019s Brain Training, only you can\u2019t play it on the toilet. &#8211; 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