Even though the dungeons seem to be infinite, the story makes the game worth playing!
This story occurs in a world which is chained by the moon and is about to be destroyed. You play the role of Capell, a young flute player who ends up arrested for being simillar to the leader of a Rebel faction, responsible for breaking the chains that connect the world to the moon. Capell gets the help of a beautiful young girl, Aya, one of the members of the faction and ends up fighting alongside her. There seems to be something else about the lunaglyphs, ancient runes that give their users magical powers (somehow similarly to Genso Suikoden)...
The game itself has an interesting battle system. Those who have already played games from the .hack series may feel somehow familiar to it. There are no time gauges, no ATB gauges, no turns. Attack the enemies until your heart's content. With the A button, you use a regular attack and with the B button you can use the Special attack, which is slightly slower than the regular attack, but causes more damage. You can also ask your allies to heal the party with Y and access the menu with Start, gaining access to items and stuff. With RB you can connect attacks with one of the members from your party to do determined tasks, such as shooting barrels or breaking rocks that block your path. You can also use LT to parry your enemies' attacks, but with all the frenetic rhythm, that will be the last thing you'll want to do.
With the X button Capell will play his flute, which will allow him to discover secret passages and treasure chests, help his allies or draw back enemies.
You can also control the camera angle with the R button while regular movements (running and walking) can be done with L button.
Each character has their own personal abilites. Other than fighting, they can also create items and weapons. Unfortunately or not, you cannot use magic, so you'll just have to rely on the mages from your party.
The story is just great, full of surprises and revelations, even though a couple of details seem to have been left aside.
There is a great amount of achievements and side-quests, which might keep you busy for quite a while. You can choose among three difficulties (Easy, Normal and Hard). Of course, the more difficult is the choice, the better are the items. There are a couple of features which are locked on Easy, so you might want to start directly in the Normal difficulty.
The dungeons are long and confusing and the maps don't seem to help. The objectives of the game (like... "where do we go now?") are frequently not very clear and you'll soon notice that you've been walking in circles for more than two hours, fighting battles which you already have fought, which can be QUITE frustrating. The map only gets complete once you've walked through that place, which can make you waste a LOT of time. The destination is not pinpointed, so if you missed what the story told you about destination, you better be prepared to spend a LOT of time trying to find where to go. Very often, they will just say "the city is located north from here", but even though you head north, you won't reach to your destination.
The battles are fast and frenetic, but you'll often get lost in the middle of a lot of lights flashing. Not rarely you'll find that you're not hitting anything because you can barely see where you are.
In spite of that, the well-elaborated story and the captivating characters will keep you playing, if not until you get all the achievements, at least until you get to the end of the game.