Nintendo has been working on a game to enter the free-to-play market for a fair amount of time, announcing last year than an early experiment with the idea would involve the Steel Diver series. The basic concept has been a game that is free to download and partially play, but requires you to pay a little extra if you want to unlock all features; this has now come to fruition as Steel Diver: Sub Wars.
The original Steel Diver — from the early days of the 3DS — was mostly a 2D game, but Sub Wars completely revamps the gameplay as it's now a fully 3D, first-person affair. The free download will give you access to two single player missions (and also a tutorial) as well as what will most likely be the meat of the game for most, a multiplayer mode which can be played both online and offline.
The controls can seem quite complicated, but once you get the hang of them you'll feel like a true sub commander. You can move around, change your speed, dive and surface, use your radar to locate enemies, fire torpedoes, send messages using morse code (a step forward for online Nintendo games in the absence of voice chat), peer through a periscope, and even use a masker to temporarily turn invisible in order to confuse the enemy. All of this can be done with either the touch screen or physical inputs, so if you don't particularly like one option you can try out the other.
The two free single player missions are rather straightforward — in one you navigate through rings in an underwater cave, and in the other you destroy enemy subs in an open ocean. Each mission has three "days" which get progressively harder, but will allow you to earn medals, which are used to unlock different paint jobs and other extras. You may also find crew members floating on the surface in some missions which, when rescued, can be assigned to work on your sub; this changes its stats ever so slightly, potentially giving you the edge in multiplayer. Some of the crew members will even come with extra special traits, like being able to slow repair your sub when it's surfaced, or always being able to see all of your allies on the map.
The multiplayer mode is almost like a very slow team-based first person shooter, in some ways — two teams of four players each attempt to take the other down in a massive underwater battle in one of several arenas. There are no respawns, so every bit of damage you can do counts. Since submarines and torpedoes naturally aren't as fast as on-land soldiers with guns, you need to plan ahead a lot, leading your shots and then getting out of trouble as fast as you can. This gives the game a strategic edge, which is a tad unusual but nice to see.
Naturally, because of the free-to-play nature of the game, there's got to be something for those who are willing to shell out a little cash. For $9.99/€9.99/£8.99 you'll get 18 additional subs and five extra single player missions. You'll also get a shop option, which has an additional five "historical" subs for $1/€1/£0.89 each. The downfall of many free-to-play games developed by other companies have been their so-called "pay-to-win" models - the stuff you can buy with money clearly being better than the free alternatives. Nintendo, thankfully, has minimised this pitfall, as none of the extra subs are significantly better - they all simply have minor differences in stats, thus making it a matter of whether you prefer a little extra speed over a little extra torpedo range, for example.
This being a fairly small downloadable title, there's not a whole lot to say about the graphics and music. They look and sound nice and get the job done pretty well, but they're not overly impressive. It must be said that all of the sound effects are nicely done, however, and really make you feel like you're actually piloting a submarine.
While the original Steel Diver was not received incredibly well, Nintendo has done an admirable job of turning a franchise otherwise destined for the scrap heap into their flagship free-to-play title. Whether or not you're willing to pay for some extra features, Steel Diver: Sub Wars features a highly enjoyable online multiplayer mode; that's something, perhaps, that the 3DS has missed so far. Since it's free, you have no excuse not to check it out — perhaps you'll even like it so much that you'll spend some money.