Four reasons you should play:
1) Best single player ccg-style game I ever seen. AI kicks ass without cheating.
2) Process of gameplay is deep. Too deep, really. I still can't win Archmage more often than 20% of times. Multiplayer guys... ghm...
3) Best level system, collecting system, and rarity system. That is, there are none.
4) Someone called R.G, Ph.D. is spotted nearby during the development.

Noob tips:
1) Read opponent's hand. He can't have your cards, he has at least one soft mass destruction spell, at least two healing/super-defensive cards, exactly one constant mana-generator, and there are combinations banned from the game, i.e. Stone Rain + Meditation.
2) Watch over opponent's mana. One big, unfortunate Lightning - and you're dead.
3) Board control is everything. Rush from turn one is only good for very few classes.
4) Phoenix assault seems OP, but is DEVILISHLY hard. Don't try it against strong opponents, unless you have ALL cards you want for it, ALL of them.
5) Elementals are STUPIDLY important. They are the goal in 50% of games.
6) Skip turns only in DIRE need.
7) Plan ahead for what you will stock mana.

This game has some of the worst DRM on steam.

You can only use it on 5 computers. ... Period.

It's cheap but it's more of a principle of the thing.

It was designed by Richard Garfield, so it's pretty much guaranteed to be a good game.

It wasn't. But he sorta tutored the team, gave some ideas, helped to design a world of the game...

Played this over and over on my phone, only low difficulties though. The cards are cool