For one reason or another it seems the Titanfall season pass is currently listed for free on the Xbox Marketplace. Interestingly enough, the deal seems limited to the Xbox One, with the Xbox 360 version currently listed at the original price of $24.99.
Odds are this is a special promotion in honor of the games one year anniversary, which is tomorrow or March 11, but you should probably download it so you don’t miss out.
Update: While the season pass is still $24.99 on the Xbox 360, you can download IMC Rising, Frontier’s Edge and Expedition for free by purchasing them separately. This strongly implies that this is an intended sale and most likely part of Titanfall’s one year anniversary. In either case, you might as well snag the DLC if you have any interest in the game.