What, you weren't sold when Nvidia announced that GTX 900-series graphics cards would now ship with a free copy of The Witcher 3? Did you think, miracle of miracles, that this already-insane deal could somehow get better?
I admire your foresight. Somehow, Nvidia has sweetened what was already an amazing deal: Starting now, any GTX 970 or 980 graphics card purchase will include free copies of both The Witcher 3 and Batman: Arkham Knight a.k.a. two games that aren't even out yet. Two of the most-anticipated games of the year, I might add.
Shots fired, AMD.
It's not just a marketing stunt. I mean, it is, but there's a reason behind it. Both The Witcher 3 and Arkham Knight heavily lean on Nvidia's suite of GameWorks effects (PhysX, HairWorks, HBAO+, et cetera) which means a machine with an Nvidia card is technically running the "definitive" version of each game, at least as fair as physics and particle effects are concerned.
It's a great deal, regardless. Subtract the combined retail price of $120 from the cost of each graphics card and you're looking at about a $400 GTX 980 or a $200 GTX 970. The latter is especially impressive, despite any qualms you might have about the 970's 3.5/0.5GB memory distribution.
Further reading: Tested: Nvidia GeForce and AMD Radeon graphics cards for every budget
You'll have to hurry though if you want to take advantage--Nvidia's only running this deal through June 1, which is a scant few weeks away. And make sure you're purchasing said graphics card from a supported retailer, to avoid any snafus obtaining your games.
Not in the market for a 980 or 970? You can still get a copy of The Witcher 3 (by itself) with any qualifying GTX 960, 980M, or 970M purchase.