Metroid: Samus Returns is a side-scrolling action-adventure game played on a two-dimensional plane with three-dimensional graphics. Players take control of series protagonist Samus Aran, a bounty hunter who explores labyrinthine environments, kills hostile aliens, and collects power-ups to gain access to new areas. Samus Returns is a reimagining of the 1991 Game Boy game Metroid II: Return of Samus; as such, it features a story and structure similar to the original game, but with new controls, visuals, and gameplay.
This instalment introduces some features that are new to the 2D Metroid games. Samus can perform a melee counterattack to deal critical damage on foes. In Metroid II, her firing direction was limited to specific angles, whereas now she is capable of firing freely at any angle. Samus also has a selection of new powers, called Aeion abilities, that rely on an energy gauge for their usage. One example of an Aeion ability is the Scan Pulse, which lets Samus scan the surrounding environment for hidden pathways and items. The game also features Teleport Stations, allowing Samus to fast travel between areas. Several abilities introduced after Metroid II are implemented in Samus Returns, such as the Grapple Beam, Power Bombs and Super Missiles.
The game features Amiibo support, with compatible figurines being based on the Metroid series. When scanned, players can unlock reserve tanks and a Metroid Marker which can be used to locate nearby Metroids. After the player finishes the game at least once, certain Amiibo-exclusive content is unlocked; such content includes a new Fusion Mode, which features Samus’s Fusion Suit and offers an increased level of difficulty, and multiple art galleries. A standard hard mode is also unlocked upon completing the game, but it does not require an Amiibo figurine.
Based on the player’s item completion rating, they can unlock the history of the Chozo race that inhabited SR388 in a series of images. After landing on the planet, the Chozo encountered the X parasites, which use the planet’s creatures as hosts. To this end, the Chozo created the Metroids using their advanced technology to combat the X parasites. Although the Chozo lived in peace when the X parasites were wiped out, the Metroids grew out of control and the civilisation came under threat. A discussion was held between two Chozo leaders; the final image reveals that one leader seemingly killed the other, standing over its body while overlooking its army.