For in-store purchase only, GameStop offers Diablo III Battle Chest for Windows for $4.97. (You must make your purchase in-store. You can reserve a copy by clicking on "Check Availability" under "Pick Up At Store", searching for and selecting your local store, then submitting your "Pick Up Person" information.) That's $15 under our June mention and the lowest price we've seen. (It's the best deal now by $25.) It includes the base game and the Reaper of Souls expansion.