Instead of Trademarking the expansion names everywhere under Blizzard, simply just have someone else do it. The internet peoples are searching to see what Blizzard trademarks. They're not searching to see what Joe from the Mail Room trademarks. Then, Blizzard can trademark as many fake names as they want. And then, after Blizzcon, Joe from the mail room transfers the real names' Trademarks back to Blizzard.