I... I tried. Got through three of the faintly mind-numbing tutorial story things (so nine, ten matches in) and couldn't keep going. Dunno if it's eternal's fault, per se*, though. Something about the general hearthstone-esq design just rubs me real wrong. I like card games of the general ilk, by and large, but for whatever reason just the raw aesthetics of it alone are a pretty serious turnoff. Didn't see anything that drew me in enough to offset that before that plus the please-let-me-stab-the-devs-for-this intro sequence ran me off
* Though those tutorial story things mentioned are borderline cancer -- one or two handhold rounds to familiarize I can accept, fif-fucking-teen (plus, counting the very first) is a bit gorram much.
Okay, yeah, the tutorial is a bit much, and I imagine they're reluctant to cut down on it because it doubles as the introduction to some major characters and their bit in the story. There's a weirdly large and detailed story attached to the game; it's not grade A writing, but the effort is there.
There's also a pretty convincing negative review up about the combined issue of massive minimum deck size, land flood/drought, and the difficulty of getting 3+ copies of the legendary you want for a deck.
I'd argue the first two are simply matters of deckbuilding skill. Getting any given card is a matter of crafting. It's a collectible card game, so not everything is available from the get-go, but the game's F2P economy is the most generous of any game I can think of. Any card you might need, provided you have enough Shiftstone (the game's crafting currency) you can just craft any card you need. There's a lot of legendaries, but they're not necessary, you can build good decks without them.
EDIT: Actually, I should add, the game got a lot more economical recently. They added a new mechanic with Merchants, that allow you to pull cards from a five card sideboard. This lets you vastly improve the consistency of your decks, with being able to exchange excess lands for gas, exchange excess gas to grab lands you need, you can keep a singleton legendary in your Market sideboard (so you don't need 3+ legends, you just need 4 merchants to grab your 1 legend), which are much cheaper and more versatile). Just so much going on in this game.