Amazon offers Prime members the StarCraft II: Battle Chest for Windows and Mac for $19.99 with free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $4.98.) That's $4 under our mention from two weeks ago (although that deal required in-store pickup) and the lowest total price we've seen. (It's also a current price low by $3; most merchants charge $35 or more.) This set includes StarCraft II: Wings of Liberty, StarCraft II: Heart of the Swarm Expansion, and StarCraft II: Brady Strategy Guide. Deal ends June 13.