Think of Soma Bringer, but even better (in terms of gameplay, as there's close to no story).
Menus: Simple, yet effective. 9/10
Story: Think of Mario and Zelda. Pretty generic. Without the actual story. It isn't necessary though, as this game was made for multiplayer. 8/10
Graphics: Top notch, and everything's customizable. There's only a handful of monsters though. 9/10
Music: Great, but nothing too memorable. It fits the environment though. 8/10
Gameplay: Delicious. it's like Soma Bringer, but much smoother and more fast-paced. You don't buy weapons/armor/any other kind of equipment, you make them yourself, with materials you've found in the dungeons. You can cook food to increase your stats (again, with materials you've found in the dungeons). You get awards (medals) for certain things you do (you get these when you pay a visit to the king). They're just to show off to friends, although when you have certain medals aligned (five in a row), you get stat bonuses and other things. The dungeons are divided in five floors each, and for a bit of money you can change them to something different (e.g. the 15-20th floor are desert, but you want to have something different, ask the cat inside the dungeon). You have to have finished those floors before you can do this though. After every five floors, you get a boss floor. There's no slowdown at all. 9.5/10
Multiplayer: Even more fun than single player. You connect with the other player, you got to his island (or yours), you get his island copied to your game, he gets your island copied to his. You can do (almost) everything you can do in single player. No slowdown unless someone's talking to a NPC while you aren't. 9.9/10
Replay value: High. You'll get addicted instantly. 8.5/10
Is it playable with zero Japanese knowledge?: Yes. My brother finished it (he's 13 years old, and doesn't know any Japanese). 10/10
Overall: Lovely game. Try it. 9/10
Images (Credit to Gamespot):
Fighting
Double sword guy running around on island
