Game is currently in development but is free to play on multiple devices. I recently picked it up on Android after checking it out very briefly on PC when it was in beta. This game is great. As someone who has spent way too much time on Hearthstone but ultimately fell off it due to a myrida of reasons, I'm really digging Eternal. Way more Magic inspired than simply Hearthstone. You play the equivalent of mana called sigils, you get to determine blockers, a lot more MTG staples as well such as fast spells (instants), and more broad enchantments (relics).
The big thing that this game is doing for me right now is it's got a way better free to play model than Hearthstone, that more heathily incorporates other modes. One of the big hang ups that Hearthstone eventually got on me was, I dislike the class system. It's not varied enough. As any experienced former MTG player would know, sometimes you like to experiment and throw different mana groups together. This accommodates for that as there is no class system just card types. But it's free to play model allows you to grind out currency in a variety of modes. There is a forge, similar to the arena you'd see in Hearthstone. But they also offer a gauntlet mode, a relatively comprehensive story mode complete with motion graphic comics that while not amazing by any regards, is a nice touch. Oh did I mention you can actually run a draft with other human players and then compete in a series of matches and be ranked on your draft?
The big key from all these modes, not only do you get rewards based on how well you do, any cards you draft in draft, use in forge to build your deck, or really any mode that has you opening packs to determine you deck, your picks in that get added to your collection on top of the rewards.
I encourage any CCG fan to check it out, it's free as mentioned and easy to get into. Certainly worthy of some grinding time just to experience.