Steeldiver is an interesting launch title for the Nintendo 3DS. The world of submarine simulation is not a particularly popular one these days, especially in the cut-throat handheld three-dimensional console world. Admittedly, no one really knew which way Nintendo were going to go with the 3DS launch and this is as novel a title as any other designed to harness the specific quirks of a new system. Let's go for a dip.

The game is composed of three main sections. A standard goal-based 'Missions' mode is the first on offer. This is the proverbial meat and potatoes of the title; a surprisingly short campaign in which you are put through your paces as an ace submarine captain. The second main section is the procedurally questionable 'Periscope Strike'. This mode involves whirling the 3DS 360degrees around you and torpedoing enemy ships (great fun on a swiveling office chair). Finally, you're given a top-down strategy minigame called 'Steel Commander', wherein you plot against an enemy force in a simplistic hex-based battlefield.

Each of the seven missions in the titular mode sees you maneuvering one of three classes of submarine through a treacherous tunnel toward an end point. The game forms itself into a hybrid of puzzle game, arcade-style shooter and frantic button-and-lever masher. All three sub classes require you to control speed, direction, depth, torpedoes and other options such as cloaking, surface missiles and cracks in your hull.

If that sounds like a lot to deal with, you've also got active volcanoes, enemy destroyers, subs, mines, falling rocks and pesky walls. Control is all managed on the touchscreen, which is an admirable design decision, even if it's a little crowded with so many things to keep under your stylus. The learning curve is well paced and only occasionally does a new player find themselves out of their depth as it were. Despite Nintendo holding this title off for a 3D launch, things operate in a two-dimensional plane - Missions mode works exactly the same in 3D as it does in 2D.

The submarines you have under your control in Missions mode range from a beginners model, the light and quick ND-01 Manatee to the ND-05 Serpent which handles like an underwater school bus, but has a whopping arsenal and all the bells and whistles you need to make the late games more dangerous runs (and defeat its bosses). The combination of devilish level design and the slow moving subs can make finishing some of the missions quite difficult indeed, not a game for someone lacking in patience. Having said that, a typical mission takes around 5 minutes to complete so it suits the public transport riding handheld gamer quite nicely. Re-playability is there in form of high score ghosts to beat and a time-trial mode with 8 courses to complete, although running through the 7 identical main mission maps three times to complete the game is a bit of a drag.

Periscope Strike makes nice use of the 3DS' feature set, requiring the player to scan a 360degree horizon for enemy ships, judging their distance with the help of 3D perception and blowing them away by pressing a big red button. This is the most accessible of the three modes and serves as a mini-game addition to the main Missions mode as well. It's fun, quick and will make you look like a chump in front of friends and family - a big hit in Nintendo's books.

Steel Commander mode feels a little tacked on, despite its more intellectual approach to the submarine game. As mentioned earlier, it's a fairly low-spec strategy exercise, sort of a hex-battleships with a couple of add-ons. Three unit types are at your disposal - subs, battleships and supply ships - each with different range, attack and repairing properties. Hunt down the AI (or human opponent over Download Play, a nice touch) and blow them out of the water using a battle engine similar to Periscope Strike. While this mode isn't mind-blowing, it's a nice little addition to the core game and makes the short main campaign a little easier to space out.

The graphics aren't anything special, the sound design is fairly standard and using the touch-controls will take a little getting used to, but Steeldiver is a solid game. For a full-priced title, you'd expect to get around 20 hours of gameplay, which the most hardcore consumer probably won't get here. It is a little on the short side, which is not helped by the lack of online multiplayer, an omission that leaves a little to be desired in this day and age.

Steeldiver is a novel and varied title that should entertain the casual gamer. At least until the Zelda games start dropping on the 3DS.