Jati, 1966, by Minnesota Mining Company (3M), author uncredited

Jati is perhaps the rarest game of the 3M bookshelf series.  Someone better-versed than I am in the history of that great decade-long venture which gave the world such classics as Twixt and Acquire could probably explain why Jati sets fetch more than $300 in auction on eBay.  Not being wealthy enough to acquire the physical game, I’m content with getting a copy of the rules and describing them here.  Happily, the game’s equipment would be quite easy to improvise.  Indeed, it could easily be played with pencil and paper -- which is a bit surprising for a $300 game -- so if you’re thinking of bidding three C-notes on Jati, you can try it out before you buy.  Although I suspect that people who pay that kind of money for a game are interested in owning more than in playing.

The object of Jati is to earn points by achieving certain configurations of tiles on a 9 x 10 board.  The configurations, called “Jatis,” are either orthogonal lines of at least five allied tiles, or diagonal lines of at least four allied tiles.  More on Jatis presently.

At the start of the game the board is vacant and each player has 18 undifferentiated square tiles of his own color, and two special tiles called booster tiles, which are neutrally colored and are marked respectively with a 2 and a 3 (or, in the original set, “II” and “III”).  The first player places a tile anywhere on the board, and thereafter a move consists of placing a tile on any square adjacent to an already-played tile.

Note that although each player has two booster tiles to place, once on the board they are neutral.  Once a booster tile is on the board, either player can use it in a Jati of his own regardless of who originally played it.

It remains only to explain the scoring system.  An orthogonal Jati is worth 5 points for the first 5 allied tiles, and 2 points for each additional allied tile:  that is, if it has n allied tiles, n >= 5, it scores 2n - 5 points.  A diagonal Jati is worth 8 points for the first 4 allied tiles, and 5 points for each additional allied tile: that is, if it has n allied tiles, n >= 4, it scores 5n -12 points.  Furthermore, if a Jati contains one or more booster tiles, its point value is multiplied by the number(s) on the booster tile(s).  For instance, if a line of 8 tiles running orthogonally contains 6 allied tiles and both of the booster tiles numbered 3, its base value would be 7 and its total value would be 63 points.  Evidently the highest possible point value for a single Jati would be a diagonal line of 5 allied tiles and all four boosters, which would score 13 x 36 = 468 points.

I haven’t played this game against an opponent, only against myself while I was constructing the above illustration.  Although I didn’t play very well, I could already begin to see subtleties arising:  you especially want to get the high-scoring diagonal lines, but you can only play a tile orthogonally adjacent to one already on the board.  Thus getting into position to make your diagonal Jati also enables your opponent to block you; unless you can somehow set up a move that poses two threats simultaneously.  Similarly, since both players can use each other’s booster tiles, you have to be careful to use them to give yourself more advantage than your opponent.  This strikes me as a game worth some attention -- someone with the time and expertise might consider implementing it on the inestimable Richard’s PBeM Server.

An alert reader who only calls himself Dino writes me that Jati was republished by a German company named Spielbox in 1986.  If you have any other information or comments about Jati, particularly if you know the author’s name, I’d be happy to hear from you.

Questions, corrections, comments:  Send me e-mail at  markthom@flash.net