Not bad
I feel you progress and level very evenly but I do have a couple things I feel need said. The diamonds are a little expensive for the quantity you get making it a little on the pay to win side which takes a little bit of the fun out of the arena aspect. And its very hard to get a red card unless you want to spend a lot of money. But all in all still does its job of killing time at work.
Darkphenomenons about
Lord of Ghosts