Amazon offers Prime members the StarCraft II: Battle Chest for Windows and Mac for $15.97 with free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $4.98. GameStop charges the same in-store pickup.) That's $4 under our mention from June and the lowest total price we've seen. (It's also a current price low by $26.) This set includes StarCraft II: Wings of Liberty, StarCraft II: Heart of the Swarm Expansion, and StarCraft II: Brady Strategy Guide.

Of note, this item is currently backordered although it can be ordered now at the above price for delivery when available.