What you can win:
Diablo 3 RoS preorder key and monthly prepaid for WoW
What you can do to win this treasures?
Nothing special. You just have to watch stream, keywords and hints will be given from time to time on stream chat on Twitch.tv. In the day of contest the person who will be choosed by rolling program will have to answer 5 questions about previously given hints and keywords. You will have to answer at least 1 question to claim the prize.
From time to time there will be small competitions for most active subscribers.
Contest will be organized every month, each month you will be able to win different prize.