Etrain Odyssey features good graphics, character classes, the unique ability to draw maps as you progress, and is hard.
You can make your own party; character classes work well and are balanced; the shop only carries items made from the stuff you find in the Labyrinth and sell to them; map making is fun and not much of a chore; free-style progression; great music from The Bad:
This game is hard. Leveling is slow, and if the whole party dies you have to start from your last save (map scribbles can be saved, but nothing else). Only 1 skill point per level means not only leveling is slow, but building up your characters is as well.
Music:
An understated feature is that Yuzo Koshiro, who worked on soundtracks for games like Streets of Rage, Sonic the Hedgehog and Actraiser, is responsible for the music in Etrian Odyssey. His synthetic style has been largely abandoned in favor of digital full symphonic orchestras, but his work represents some of the best of what we used to listen to, and he's done a fine job here as well.
Story:
There's not much story, which is great if you've had your fill of being lead around by the nose. You are free to go where you will and do what you will. The characters are all drawn well.
Mapping & Exploration:
Exploration feels good as you progress through the Labyrinth and map your way around. The ground draws for you but you have to draw walls, encounter spots, treasure spots, and annotations. A cool feature is that some map points will notify you as you are moving onto them the next time you come towards them, popping up on your screen what you wrote.
Leveling and Encounters:
The game gets easier as you level up, but every once in a while an encounter will cream you. I've found that certain creatures are just impossible to take down without a balanced party, or - if you know what you're going to face, an overbalanced party filled with the classes that beat that beast best.
Naturally, characters not in the party (or in the party, but dead) don't gain experience.
Save Game:
There is only one save on the cartridge, due to the amount of map data possible to save; however, you can have 20 characters in your guild, so my 10yo daughter and I still play with our own "parties." Missions and party inventory is the only conflict, but the former is not essential.
The main negative to this game is the inability to save the game. You can only save in town at the inn (some areas of the Labyrinth feature warp points). This seems counter-intuitive on a Nintendo DS handheld gaming system; sure, this is the way these types of games used to work, but we used to sit for hours in front of our computers playing them, not on the city bus or while following the family shopping cart like a zombie.
Sequel?:
There is a password feature which, supposedly, will be used to somehow transfer some part of your progress to a potential sequel to this game. Don't hold your breath, but it would be nice.
Summary:
A worthy buy if only because the game is so well done and balanced. Just expect to close your NDS when shopping and put it in sleep mode, and expect to curse a few times as you are learning and get your party wiped.
The game is hardcore, without being so hard you don't want to play it.