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. :)