Game within a game

Well, a game of Chess is really a battle of the minds, so opposing intelligence-checks is an easy way to go, say three wins wins the game, either cumulative or consecutive, or maybe even the first character to lead by three over his/her opponent.

Proficiency here might be hard to make obvious at first, but playing against someone who isn’t proficient might mean the un-proficient player rolls at a disadvantage. Of course if neither player is proficient then they have no disadvantage since they are playing each other and not the board. If someone is proficient and has really high intelligence you might lower the successes needed to win for that player, in the same sense as good players of chess will outclass a lesser opponent in fewer moves.

What’s important here is that a game of chess differs from a game of chance, like dice, in that you are playing your opponent, not the game. In that sense, you might want to give your players the opportunity to attempt to deceive their opponent, making an extra opposed deception/insight check on a success if the player wants to. This would simulate bating the opposing player into a trap and, if successful, might impose disadvantage on the opponent.

This whole thing is rather of the cuff and would take some testing. No doubt it might be difficult to narrate this in an exciting manner. Would be fun to hear how things work out though!