Play Rise of the Tomb Raider from 10/11 - 10/18 and get 100,000 free in-game credits used to purchase Expedition Card Packs. Valid for 360, X1, PS4, and PC.
Ok, you don't even have to play the game. Load the game, go to the marketplace on the main menu, tab twice to the right to the present icon and collect the 100,000 from the gifts. You can also get another 5,000 if you played Thief.