Quote from Crystal Dynamics:
"We want to apologize on behalf of all the gamers who enjoy to obtain achievements in games, and we would like to publicly state that we made a mistake in making 1/3 of the game's achievements revolve around the multiplayer when our game was intended to be single player oriented.
We are currently making progress on Tomb Raider, and we will not make this same mistake again Thank you all for being faithful fans of Tomb Raider, and we hope you will enjoy our adventures with Lara to come." -Crystal Dynamics