What would signal the development team was out of tricks?

If you play or played Magic: the Gathering, you've heard of the Power Nine: cards printed in the beginning of the game that were insanely broken. Cards so powerful that their presence is felt in the game to this day. Cards that, naturally, players would love to see reprinted. However, it's been pointed out that if they ever are reprinted, it would be using the biggest and most obvious idea that the game has. It would be something that would bring in a lot of old players, attract people, spark interest, and there would never be a way to top it.

There are certainly things that reek of having the sense of a great trick that could only work once, something the players have long asked for but has always been avoided. World of Warcraft's reconstruction of the old world and Final Fantasy XI's expansion to the long-awaited Level 99 level cap both look that way to some players. What would convince you that the developers were cashing in on the one last thing that players have been waiting for? Would it be enough to bring you back, or would it signal to you that the game was dying?

TH