I have been playing EOS knights and it is pretty hands off. All you need to do is manage your material after every round. The material that gets 'dropped' after each round can be sold on the open market or used to upgrade your knights. As the knights upgrade the chance of getting better drops increases. I have spent more EOS than I have received at t his point, but I have started to get some pretty good drops now that I am at a higher level.
It is a potential way to mine EOS... but it does take some initial investment. So do S9's is suppose. It is worth looking into for sure!
If you are going to play, contact me and I can get a 'referral bonus' which will score both myself and you 1000 magic water (which is required for levelling up in the game).
I look forward to hearing your thoughts.