Well I know this isn't the same thing I'm about to tell you but I doubt you will be successful with trying to exploit online games by spiking it's updates. First you would have to find a game which distribute its autoupdates as executable then pwn their update server and change the binary. Most of them simply download it's own package format and extract the files not mentioning that the programmers probably do implement integrity check on the client side.

So there is a site called mmowned where you can buy/sell/trade stolen accounts, what you can also get easily with password stealers if you doing ppi in big... You can sell online mmo accounts as high as 800Euro/1 account depending on the characters. If any of you involved in selling these just drop me a pm, I can provide you with them. Of course you need to be an experienced seller and know a lot about the game, forums, community to sell them, also need good social engineering skills for this.