Much like Zero Mission was for the original Metroid, Metroid Samus Returns is a reimagining of Metroid II: Return of Samus for the Game Boy. Samus is called upon by the Galactic Federation to go to planet SR388, in hopes to rid the universe of the most threatening creature in the galaxy once and for all: the Metroids. In collaboration with Nintendo, this game was developed by Spanish company MercurySteam, who also made Castlevania: Lords of Shadow – Mirror of Fate, another 2.5D Metroidvania title for the 3DS.