Seems like pay to win. Can I compete without paying?

Yes and no. You can play for free but you would have to be okay with leveling slow. I would say paying males you gain more though. I would at least buy a small chest of oban. Each day there are 3 chest 2 cost 1 oban the other 2 oban you can purchase one of each of two and 2 of the the 3rd one totaling 5 oban a day. Each have stratagem which are much needed.