Metroid: Samus Returns is one of the big surprise announcements that Nintendo had up its sleeve for their Treehouse stream today. The game is a re-imagining of the 1991 Gameboy game Metroid 2: Return of Samus that will be coming to the 3DS and 2DS. Samus Returns will be a 2D side-scroller in the same way as the original Metroid games and is being developed by the same team behind Castlevania: Lords of Shadow.
In the game you play as Samus Aran (duh) who has been sent to planet SR388 by the Galactic Federation to investigate the appearance of Metroids on the planet and destroy them. The game has heavy focus on exploration and discovery as you try to uncover the mystery behind the Metroids as well as discovering new equipment and the newly added Aeion abilities. Aeion abilities are much different than suit upgrades such as the Scan Pulse that reveals the a bigger chunk of previously undiscovered map on your lower screen as well as showing off hidden pathways. Aeion abilities require Aeion energy to use so you won't be able to just spam them anytime you want. Other new additions include the ability to freely aim your cannon anywhere on the screen to aim more accurately, and a new melee counter that allows you to fend off enemy attacks and get in critical hits when timed right. In keeping with the theme of exploration you'll encounter places and objects you won't be able to interact with since you don't have the correct ability or key, so you'll now be able to add pins on the map to remind yourself where you need to return to when you've gained new abilities. Teleport stations are a new addition as well that will allow you to teleport to previous and current areas so that you can avoid long backtracking journeys.
Along with new additions and updated graphics, two of the composers who worked on the classic Super Metroid have returned to work on the soundtrack and music for Metroid: Samus Returns. The original enemies from Metroid 2 have all seen redesigns to allow them to have updated looks as well as new abilities and attacks to allow the game to feel fresh while still having that classic Metroid feel. The map of the game itself has seen a redesign as well in an effort to make it more dynamic and diverse in the way players have to play the game in order to progress.
In a tweet by the official Nintendo Twitter announced that the release date for Metroid: Samus Returns will be September 15 for 3DS and 2DS. Along with the regular game there will also be a special edition that includes a CD with a collection of Metroid soundtracks from all the previous games.