I know we have too many chess variants already, but I thought of another interesting variant that would give a new spin on the traditional chess strategy.
It would be called Armor Chess, because the only different rule is that each player starts out with one piece of armor. on the first turn of the game they choose one piece to wear the armor for that game. That piece then will not be captured the first time it is attacked by an opponent's piece. Instead the armor will protect it and it will capture the attacking piece. Once this has happened once, the armor is used up and that piece is not like a normal piece and will be captured the next time it is attacked.
notes: Because the king is never technically captured, just put into checkmate, you cannot give the armor to the king. Also, my first thought was to make the armored piece unknown to the opponent, but that would cause certain difficulties, mostly with a check situation where you try to capture a piece to take the king out of check, but that piece does not end up being captured, so I think the armor would be visible to the opponent.

any thoughts?