I am a creator of Chess variants. Chess variants, which I sometimes abbreviate as CV, are games that look like chess but aren't. They often share some characteristic on chess: a checkered board, pieces that move in a particular way, and so on; but they have differences that make them decidedly not chess: different pieces, different game boards, even different numbers of sides.
There are some more examples of chess variants not of my authorship here.
Flow of creating chess variantsEdit
The most important part of chess variant creation is the central idea – be it part of a conworlding exercise, something funny that you have the need to implement into the stereotypically boring world of chess, or even seeing what kind of game you will end up with by adding a random adjective to the world "chess": "spicy chess", "French chess", "chess of the Altiplano" — what are the games behind these names?
First are the settings: pieces, boards and number of sides. If it is a TV show or something, then just make a character a piece, or if it is a geographically-themed one, mess with the board shape. A lot of setting things can be made to make the game more thematic.
The pieces are difficult. Assigning a move to a piece is at best a hidden pun (via copious use of Betza notation) and at worst completely arbitrary. If the armies are unequal then you must make them add up to the same; this is equivalent to having a giant chain of +s, −s, ×s ands ÷s written down in front of you and the slip of paper containing them stretches as far as the eye can see, and you are told to write down a list of numbers (of which at least some portion of them come from a predetermined list) which will make the entire sum work. Oh, and you're only given a pen and no correction tape...
And of course you also have to figure a powerful (but not too powerful) promotion sometimes, when the situation calls for it.
Finally you are to playtest it. I never did this part, partially due to too much work, but mostly due to no one willing to play with me.