In Spades, the variant "Spades mirror" means that each player must bid exactly the number of Spades cards she got.
This variant remove the bidding phase of the game and leaves only the playing. Sums of bids are always 13 and players have knowledge of how many spades each player poses.
My question is, what are the main differences in the game play from the regular Spades, I mean how my strategy should change?