It's pretty much a knockoff hearthstone. Pretty much all the mechanics are the same as far as I'm aware, which makes it easy to pick up, but hard to sell on why anyone would play it.
There is a game Shandalar which is "MTG but singleplayer" which has some fans and I was thinking a Hearthstone version would be similarly interesting.
I wonder if Dungeon progress x/7 which fills up would be enough for people to try and beat each dungeon.