I was thinking with these mystery game giveaways, it might be kind of nice if ModBot had an optional MYSTERY rule, where you could enter the actual game names in your "register" PM, but the new rule would cause all of the games in the giveaway to show up as mystery games. Then ModBot could do one (or both) of the following:
(1) Reveal the game name in the post edit after the raffle is over
(2) Reveal the game name to the winner via PM
A feature like that could prevent "wasted" Humble Links, for example, where a winner already owns the game but can't possibly know it until they use the link, thereby rendering it useless.
Definitely would be a good feature. (1) would be useful for the giver too, in case they had to track down games that no one happened to claim.