This week’s shining example of Cross-Brand Synergy Optimization comes via Blizzard, who announced yesterday that the new Hearthstone hero Liadrin will only be obtainable if you have a World of Warcraft character.

Liadrin, who is a cosmetic upgrade and doesn’t add new abilities to the popular digital card game, will be unlocked for anyone who gets a World of Warcraft character to level 20. You don’t need a subscription—Blizzard says using the free Starter Edition works just fine—but you can’t get the unlock retroactively, either. You have to have gotten to level 20 after March 11. Synergy!

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