If a game is described as “frenetic,” what comes to mind? A twitch-shooter, the most recent Burnout, or maybe a fast-paced fighting game? Surely you wouldn’t think “sudoku.” But sure enough, Zendoku for the Nintendo DS manages to take the classic, cerebral puzzle and turn it into a frantic martial-arts game. But is it fun? Well, that depends.

The numbers have been replaced by Asian symbols such as dragons, swords, and pandas, but otherwise it’s straightforward sudoku; a 9x9 grid split into nine 3x3 grids, with each symbol appearing in each grid, row and column exactly once. Each character has a fighting game-style health bar on the top screen next to their character portrait, and attacks are launched by filling in complete grids, rows, columns, or by placing every instance of a particular symbol on the entire board. In addition to causing damage, attacks force your opponent to complete a quick touch screen-based minigame before continuing to play. Wrong guesses, however, damage whoever made them, heal their opponent, and automatically fill in a few of their opponent’s blank squares.

The basic single-player mode is Quest Mode, in which your character travels across the land getting into fights, much like in a fighting game. Each character has their own storyline, including dialogue before and after each match. The stories are tongue-in-cheek parodies of fighting games and martial arts movies, with some genuine laugh-out-loud moments and also a decent amount of groaners (one boss’s dialogue, an extended reference to the “Chuck Norris” jokes that were very popular a while back, is pretty dated).

Although Quest Mode starts off ridiculously easy, by the end it gets frustrating hard. As in, “throw your DS against the wall” frustrating. In addition to pitting you against enemies who are supernaturally good at sudoku, the game also increases the difficulty and frequency of the touch-screen minigames, which are just long enough for you to forget what you were doing on the sudoku board. Just about the time you remember what you were doing, the game hits you with another minigame. It’s a recipe for frustration that causes the game to cease to be fun in the later levels.

In addition to Quest Mode, there are a variety of gameplay formats. There’s a training mode for those just getting started, which teaches the basic sudoku rules as well as Zendoku-specific attack tips and techniques. Zen Mode is essentially a time attack, where the player tries for a high score against the clock. Attack Box lets you unlock new “attacks” aka minigames, for use in Quest Mode. There’s also Classic Mode, for those who just want traditional sudoku puzzles presented in a straightforward manner. The standard numbers 1-9 are back, and all graphics and frivolities are stripped away. Puzzles are even randomly generated, so there’s plenty of sudoku for anybody.

As with any fighting game, though, the real meat of the title is in the multiplayer section. In either single-card download or multi-card play, you have the option of cooperative or battle modes. Cooperative is an interesting mode, in which each player controls four of the nine symbols and a fifth that can be used by either player. Players then team up to fill in the whole board as quickly as possible. Although it’s an interesting diversion, cooperative mode won’t hold your attention for long. Battle Mode, on the other hand, is a whole different story. It’s set up the same way as Quest Mode, with attacks launched for successfully filling in your board. Playing in this mode really does give you the same intense feeling you’d get from a good fighter, and beating your friend with sudoku is a genuinely satisfying moment.

Zendoku tries hard to be the be-all-end-all DS sudoku title. True, there are some problems with the single player modes, but with an infinite amount of puzzles, this is a decent value for any sudoku fan (although other DS sudoku titles have better interfaces, such as Brain Age’s handwriting recognition feature). Anybody who can talk their friends into sudoku deathmatches, though, will be glad they did. There’s a great deal of fun to be had filling in boxes and beating your buddies up.

Gameplay: 7.3
The sudoku gameplay isn’t going to throw anyone any surprises, it’s sudoku. The martial-art style attacks and the minigames add a fun element to the game, until they cause the single player mode to become so frustratingly hard that the game ceases to be fun.

Graphics: 6.5
Characters are represented by high-detail, super-deformed martial arts characters. Other than that, most of the game’s graphics consist of a 9x9 grid with Asian symbols on it. It’s not going to blow your socks off, but it’s functional.

Sound: 6.7
As with most elements of this title, the music and sound effects are parodies of those that you’d find in your average chopsocky flick. As such, generic kung-fu music and combat noises comprise 90% of the audio in the game. You can decide if that’s a good or a bad thing.

Difficulty: Hard
Like, crazy, frustrating hard by the end of the game. So much so that it stops being fun. The sudoku itself, though, can be adjusted from Easy to Master, aka very very hard, so there’s a challenge for anybody.

Concept: 7.6
Spicing up sudoku with DS-specific features, like minigames and wireless multiplayer, was a good idea. Kung-fu parodies can be funny, sometimes. Combine the two and you get a game that works relatively well, most of the time.

Multiplayer: 8.5
Battle Mode comprises about 85% of why this game should be bought by itself. I had no idea competitive sudoku could be this much fun.

Overall: 7.7
Zendoku is worth picking up if you’ve got buds that will play with you. Fun multiplayer kinda makes up for a lackluster single player experience.