Old-school, 2D, Action RPG. Zenonia Killer? Yes!
The story is long and involved (and cheesy in places) but the game works superbly well as a "pick up, put down" RPG for those on the go (great auto-save), and as a "marathon-session" RPG, because of the carefully thought out mechanics.
The action is frantic, the levelling system and UI are intuitive, and the coin and item exchange system are fun, adding a new dimension. I didn't buy any IAPs but exchanged items with other player on-line quite a bit.
It can drag a little if you're not into grinding to level-up, but that's a general trait of the genre. The story might lose a little in translation sometimes (it's from Korea) but overall, it's polished, addictive and fun. Definitely worth adding to you iDevice.