The perfect union of puzzle and RPG mechanics makes for an excellent and innovative experience.
Graphicswise, the game is as simple as you can expect from a normal puzzle game. While the character portraits, or avatars, have no frames of animation at all, they're excellent works of art. Also, the world map of the game looks more akin to a U.S. road atlas than someting from an RPG, but that is only a minor flaw and not a really glaring one. The puzzle pieces, as one can expect, consist of jewels, skulls, purple stars and the occasional multiplier piece for quickly increasing mana.
As far as sound is concerned, it can be either a blessing or a curse. Sound effects are very minimal and there's only a few clips of voice acting. What redeems it is the melodic soundtrack, which plays songs at random intervals.
Controlwise, the game is very intuitive and simple to learn. To play the battles out, you have to touch a piece using the stylus and touch the piece next to it to swap them, hopefull to a couple pieces that are the same color as the first piece you touch. The touch screen is also used for casting the game's multitude of magic spells, given that you have the neccessary mana of the right colors to cast the spell with. An interesting, yet useless control scheme is holding down either the L or R button to swap the two DS screens with each other.
Regarding the gameplay, it is extremely addicting. The game boasts a grand total of over 150 quests, most of which are optional sidequests to increase your experience and gold reserves. The game also gives you the opportunity to capture any of the monsters by figuring out a "clear-all-the-pieces" type of puzzle, difficulty depending on the type of monster. Once you successfully captured a monster, you can research and learn it's spells or use it as a mount around the world, again depending on the type of monster.
Overall, the game is definately worth it's price of admission, and deservely so, as the gameplay is so addicting, you won't be able to put it down for hours to come.