You might be able to order a retail boxed copy of the game from out Blizzard Store but we do not sell cd-keys separately. No one out there is authorized to do so. If you find a site, and they exist, that sells keys, be forewarned. They often sell illegal, invalid, muted, or disabled ones. They also tend to sell the same keys to multiple people. Unless you get or have an original key on the Blizzard label, there's no warranty for it.
You also won't be able to mix media types. You have to use either cds for both games or the digital download versions.
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