For game makers, deciding whether to charge for certain content in online games can be a tricky balance between fostering player loyalty and making some quick revenue. The game's lead producer Chris Hager said that NC West -- the Western division of the South Korean company -- discussed charging extra for the expansion, which raises the game's level cap, adds new instances and zones, weapons, items, skills, pets and other features. But in the end, the company thought that giving the expansion for free to paying subscribers would be beneficial in the long run. "There was discussion about whether to charge or not," Hager told Gamasutra. "I think what it came down to was that we felt it offered good player value, to give it to players for free, and we just wanted to make sure that if in the future we ever do charge for anything, we make sure it's a good amount of content. We don't want to nickel and dime players."

Hager may want to avoid "nickel and diming" customers, but if a price tag is closely aligned with players' expectations of that content, is customer goodwill really at risk? Earlier this year, World of Warcraft developer Blizzard charged $10 and $25 for two different in-game mounts, and generated a dollar amount estimated to be in the millions. It may have been a turn-off to certain players, but many others happily queued up to buy these virtual items on top of monthly subscription fees."Blizzard has a large install base," said Hager, "and I think that especially the one pet [the Pandaren Monk] where they took the proceeds and gave them to charity, I think that's awesome. I'd love to be able to charge $10 and give half of whatever we make to a charity, because I think that's a worthwhile cause."