Minichess

[1] The motivation for these variants is to make the game simpler and shorter than standard chess.

In 1981 mathematician David Silverman suggested a 4×4 chess variant, as shown on the diagram.

[5] To make the variant more playable, Silverman finally proposed to insert a row between pawns and use the board 4×5.

The 1995 game Tic Tac Chec, invented by Don Green, is played on a 4×4 board which starts empty.

A board needs to be five squares wide to contain all kinds of chess pieces on the first row.

[9] Later AISE (Associazione Italiana Scacchi Eterodossi, "Italian Heterodox Chess Association") abandoned pawn double-move and castling.

The game was largely played in Italy (including by correspondence) and opening theory was developed.

The statistics of the finished games is the following:[4] Mehdi Mhalla and Frederic Prost weakly solved Gardner minichess in 2013 and proved the game-theoretic value to be a draw.

Paul Jacobs and Marco Meirovitz suggested another starting position for 5×5 chess shown at the right.

Jeff Mallett (main developer of Zillions of Games) suggested a setup in which White has two knights against two black bishops.

[12] Mhalla and Prost proved Mallett chess to be a forced win for White in 25 moves, although theoretically the game is drawn when played perfectly if White is given the bishops and Black the knights rather than vice versa.

The game was sold by Amerigames International and received National Parenting Publications Award in 1993.

Miccio advocated these games as educational tools for children to learn chess rules.

Chess Attack, which has the same setup as Gardner minichess (but played on a bigger board) is sold by Norway company Yes Games AS since 2008.

MinitChess, published in 2010 based on earlier 2007 and 2009 variants, is played on a Gardner board with the black pieces mirrored.

This variant is intended to be easy to write computer programs to play and harder for expert human players of standard chess, while still retaining the essential character of the game: several computer tournaments have been held.