Use your king

Your king is often the centre of attack in the opening and middle game phases of a chess game. You must hide it behind pawns and other pieces for it's own protection.

However, the king is a fighting piece in its own right. Only when most of the major pieces have gone can it enter the endgame because the board is a much safer place. The king should enter the endgame because every fighting resource is usually required to push a pawn to promotion.

The only lone pieces a king can never move next to are a king and queen. I just thought of that.