Starts with the letter 'M'
- Mad Elephant Chess. Pawns can be turned into Elephants; Elephants can promote to Mad Elephants, and Mad Elephants can trample lines of pieces. By Peter Aronson.
- Mad Scientist Chess. Fetch me the Pawn, Igor! (8x8, Cells: 64) By Peter Aronson.
- Maelstrom. All 64 squares of 8 by 8 board are initially filled with pieces. By Michael Asher.
- Makarenko's Chess. Pieces are stacks which can be split and combined to create other pieces. Author: Jacek Dobrzyniecki. Inventor: Anton Makarenko.
- Mamra Chess. Adds the Mamra, a piece that only Pawns may capture. (8x8, Cells: 66) By George Tsavdaris.
- Mangonel Chess. Introducing the remarkable Mangonel piece, which can hurl pieces over its head, on a Gustavian board (zrf available). By M Winther.
- Martian Chess. Two or four player strategic game with chess elements played with Looney piramids. (4x8, Cells: 32) Author: Hans L. Bodlaender. Inventor: Andrew Looney.
- Martian Chess, Jetan. Large variant from the book The Chessmen of Mars. (10x10, Cells: 100) Author: Jean-Louis Cazaux and Hans L. Bodlaender. Inventor: Edgar Rice Burroughs.
- Mastery . A Game of Skill for Two Players. Inventor: S John Ross.
- Medieval Chess. Missing description (8x8, Cells: 64) By Daniel Robert MacDuff.
- Mercury. War on Mercury between many weird creatures. (8x8, Cells: 64) By Daniel Robert MacDuff.
- Meridian Chess. Introducing the Meridian, bishop-capture combined with bifurcated bounce-move, on an H-board (zrf available). By M Winther.
- MetamorphaChess . Pieces represented by dice change to another type after having moved. Inventor: Robert Dubisch.
- Metamorphin' Assimilation Chess. A hybrid of Metamorph Chess and Assimilation Chess. By Fergus Duniho.
- Metamorphin' Fusion Chess. A hybrid of Metamorph Chess and Fusion Chess. By Fergus Duniho.
- Mind-Vector. Missing description (9x9, Cells: 81) By (zzo38) A. Black.
- Mir Chess. Missing description (8x8, Cells: 64) By David Paulowich.
- Mockery Chess. Missing description (8x8, Cells: 64) By Stephane Burkhart.
- Mortal Chessgi. A Chessgi game in which captures reduce material. (8x8, Cells: 64) By Fergus Duniho.
- Mortar Chess. Introducing another piece named Mortar, a form of cannon, on an H-shaped board. Positionally advanced. With zrf. By M Winther.
- Motorotor. Variant where two platforms slowly orbit a central board. (11x11, Cells: 43) By Gavin King.
- Mulligan Stew Chess. 42-Square Swapping-Mage Teleporting-Assassin Dual-Color-Bound-King Limited-Double-Move Leaping-Pawn Chess. (6x7, Cells: 42) By Peter Aronson.
- Murmillo Chess. Introducing the Murmillo piece, and new collision-capture, on a Gustavian board (zrf available). By M Winther.
- Musketeer Chess. Adding 2 newly designed extra pieces. (8x8, Cells: 64) By Zied Haddad.
- Mutant Chess . Pieces mutate during the game.
- Mutatis Mutandis. Astonishing variant featuring 22 different changelings at random setups. (8x8, Cells: 64) By Carlos Cetina.
Total items listed: 26