The "Explorer Card Pack" DLC for the upcoming game "Rise of the Tomb Raider" (Xbox One) is free via a redemption code obtained in the link.
To obtain the code, click on the eight icons on Lara's wall and the page will pop-up with a 25-digit code that states "Save this code and redeem on or after 11/10/15". For us, that's the 10th of November. You cannot redeem it before then.
When the time comes, redeem the code by logging in here.
And pants. Enjoy!