I was thinking we weren't even planeswalkers: what I was thinking is we're dudes part of the Transguild Promenade, we don't even know about Bolas. Then we accidentally mess up Bolas' plans and shit goes doooown. From there we would be eventually awakened. However if everyone prefers, we can already be planeswalkers. The thing is, starting as planeswalkers, we really wouldn't have formed the Transguild Promenade cause we're not even from Ravnica. 

Also also I will be creating elaborate and strong rules for the use of mana. Give me a bit for those.