Kid Icarus was always a bit of a weird game. Originally released alongside Metroid and using an almost identical game engine, it was quickly overshadowed by the popularity of Metroid's giant game world full of areas to explore and, save for a (more entertaining) Game Boy sequel, the series was never heard from again until Pit suddenly appeared in Super Smash Bros. Brawl.
Although Metroid started off as the more popular game after its release, it's clear today that Kid Icarus has aged a lot better. A giant world to explore was cool at the time, but with all the refinements similar games have had since — such as, most importantly, an in-game map to prevent getting lost — the original Metroid has aged rather poorly in comparison.
3D Classics: Kid Icarus is currently only available in Europe to users who entered a Mario 3DS giveaway; it is not available to purchase separately, but will be released to the wider population later this year.
Perhaps the game's most unique feature is that it has four different kinds of gameplay. It starts off as a vertical scroller for three stages, leading you to think that that might be all it is, but you then enter a fortress in which you must find and defeat a boss. Metroid comparisons are inevitable, but these fortresses aren't that big and are generally a lot less confusing, plus you have access to a map. The middle of the game changes things up again, and is actually a horizontal sidescroller instead of vertical, while the very last stage does something else entirely.
This game would've been compelling enough, but there's also plenty to find and do around the levels. During your journey you'll come across special rooms, such as a spa that restores health, one of two different stores, a challenge room where you must endure a seemingly endless flurry of flying tiles to receive a power-up. You can also acquire hammers, which will allow you to smash soldiers imprisoned in stone in the fortresses, causing them to assist you in battle against bosses. They die quite quickly, however, and usually end up being useless.
Aside from the frequent change of gameplay styles, Kid Icarus also often mixes things up with new area designs. Most levels have their own unique tiles, or at the very least use a different palette, while every individual world has its own unique set of enemies. There's even one enemy type towards the end of the game that looks like a Metroid.
Now, if you're rather knowledgeable about old Nintendo games, you might have been aware that, when Kid Icarus was originally released on the Famicom Disk System in Japan (rather than the standard Famicom) it was one of the first games to feature the ability to save your game, with three slots available, which was also the case for the FDS version of Metroid. When the game was brought over to the West, however, Nintendo could not find a way to fit the saving ability on the cartridge (with cartridges allowing for less data than disks) and as such, had the save feature replaced with a password system. They would later figure out how to keep the ability to save for The Legend of Zelda, among others.
This being Nintendo, it should be no surprise that the 3D Classics version of Kid Icarus has been based on the original Japanese release. The password system you're probably more familiar with has been removed, and the three save files originally present have been reinstated. There's also an added high score table, adding a bit of replay incentive, though it's rather easy to simply farm for points in the game.
One curious thing about the original Kid Icarus was that its backgrounds were completely black. That wouldn't work so well with 3D effects, so Nintendo and Arika created some backdrops specifically for this version. They're a bit of a mixed bag, really — the indoors backgrounds go perfectly well with their surroundings, but most of the outside ones look a bit out of place, with much more detailed spritework than the foreground, which survives completely unchanged from the original game. But they at least do what they were intended for perfectly: the 3D effect sticks out well and works nicely.
The music, quite obviously, has not been changed at all, but we have to point out that, for some reason, the game's volume seems to be a lot louder than other 3DS games. We actually recommend not playing on max volume, as it can become painful to the ears.
Kid Icarus was always a lot of fun, but for some reason it never really reached huge levels of popularity like its cousin Metroid. This 3D Classics version is almost identical, but small additions and tweaks like the new backgrounds, 3D effect, high score table and save files ensure that it's worth a look even for those who already played the original to death. Now, about that Game Boy sequel on the 3DS Virtual Console...