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It is sad if it is gone from free play. Enough folks will buy Lumosity but the freebie is good word-of-mouth marketing. To take it down is a bad rather than good business move. Few will decide that it's a must-have to purchase, esp if they don't play other Luminosity games. And the bad taste from losing a freebie will be a detriment not an enhancement to their reputation. Better to keep it up and allow free play as folks are likely to mention Luminosity and how much they like their games if they're allowed to play at this one-off level.