It's a really great trading card game for iOS and Android, and I'm obsessed with it.
So much to the point where I carry my phone with me EVERYWHERE and check it every hour or so.
Haven't played it yet? You should give it a shot.
If you enter this referral code, you won't only be helping me, but giving yourself an awesome head start of 100,000 rupies (in-game currency) and a rare card called Angelic Knight.
Referral code: uki68524
If you're already playing the game, or want to start out, I made a quick tutorial on how to make in-game items and rupies!