Throwing in some games with an expensive graphics card has proven to be a highly successful sales strategy for AMD. The "Never Settle" bundle encompasses a wide variety of games; the graphics card buyer can chose a certain number of them, with how many exactly depending on the specific model of graphics card. You can even get some indie games this way.
Nvidia has been trying to catch up by giving buyers in-game bonuses for some free-to-play games such as Heroes of Newerth and Warface. Now, Nvidia is trying to make the GeForce GTX 770, 780, and Titan more attractive by including The Witcher 3 with them.
Nvidia’s possibly nervous that nobody’s going to buy these three graphics cards in the coming weeks because the first 800-series models are slated to be introduced in September. Usually, the model with the highest performance is first, which would be the Maxwell-based Nvidia GeForce GTX 880 in this case.