For a free card game, this one's pretty cool.
I just totally dig the animated cards. It's something most digital card games could have, but only few actually seem to do. heh, and effects like having cards with flying ability float... it really breathes that extra bit of life into those card games.
As for the game itself, it's pretty straightforward. There was this youtube tutorial... but I totally skipped it. I'm not fond of video tutorials, rather have a written guide. But neither was necessary, it just takes a few rounds and a test build deck to figure out how things work.
There's also a few tutorial matches you can play to learn the ropes.
This is a multifaction cardgame; meaning that, much like MtG with their different elements, this game has different factions. And ofcourse each has their own way.
The way you choose your factions is by giving creatures of that faction a commander position. This allows them to be on the table and use abilities, but they're not directly on the battlefield. Some cards seem to need more than one commander and only a max of 3 commanders allowed, so for the really powerful stuff you'll need to choose.
Resources on the other hand are automatically added; rather than needing resource cards, you get incremental RP each turn in the game.
The "battlefield" consists of a commander field, support field, and combat zones (defense/offense).
You can freely move your creatures around each turn, even their attack order can be sorted. Support field is where you can place creatures outside combat, it's also where most creature cards start.
Player turns go in 2 sections; preparation and turn resolve.
Basically, each player prepares a set of moves, and then that turn is set into motion.
Rather than turn based and being able to interrupt the other players' turn to use instant abilities, they have to be prepared up front. This does make it harder than waiting for the right card, you also need to be sure your target will become or will stay available when you aim for them.
Apart from PvP, there's also a campaign available. It's best to start off there with the first few levels of each campaign, as you get a starter pack from each one.
I haven't been playing much yet, so I can't say much about the balancing issues some people have been talking about.
Either way, as this is still a beta, I'm sure eventually the whole set will get balanced eventually.
All'n all, it's been pretty good so far.