Game payment options

The prerequisites are:
1. The game is a MMORPG (Massive Multiplayer Online Role Playing Game) that you want to play
2. The average fee (for all players) should amount to 50$ per year
3. Micro payments would mean that paying gives you an advantage compared to those that do not pay
Given these prerequisites, what would be your preferred way to pay?
    This is a required question
    This is a required question