Offside determination requirements
- time and causality, we need a point in time to check the offside rule - most likely
- a goal - the king could be seen as kind of a goal
- at least a 1d coord system to determine if a player is offside - check
- a penalty zone - debatable
- players in at least two teams - multiple
- a ball, that is shot to a player behind the last line of enemy players - No.
No ball, no offside. Chess with a ball could be interesting, though. :)