Skirmish Chess

Skirmish chess is a redesign of chess, intended to distill what makes chess fun in a short, 10-minutes-or-less experience. It was created for Game Dev Club's 5x5x1 game design challenge in the summer semester of 2017.

Skirmish chess is played on a 4x4 board and follows these rules:

First, set up so that the board looks the same as the one pictured above. Then, starting with the player who will make the first move, each player sets up any of their remaining pieces on the blank squares on their side.
You may never have more of any piece than are included in a standard chess set.
No special rules aside from pawn promotion. This means no castling, en passant, etc.
Otherwise, skirmish chess is played the same as normal chess.