Summary pulled directly from Steam - Some text may only be applicable to Steam platform

Cosmos: Stella Returns is the sequel to Cosmos Bit. At last more of Cosmos' lore is revealed thanks to a new story and improved graphics. Furthermore, the space warrior Stella Mironova can sport new moves and accessories to prevail in this new adventure.
As its predecessor, Cosmos: Stella Returns offers retro looks and gameplay, adapting its difficulty to both veterans of the genre and the less experienced players.

• New 90s pixel art graphic style!
  
• New accessories to discover!
  
• A new star-collection system to improve your equipment!
  
• A tribute to the Metroidvania genre!
  
• Retrogaming pixel art style!
  
• 7 fearsome alien bosses!
  
• 10 extra space cards to be found!
  
• High level Synth Wave soundtrack signed by Jake D. Bind!
  
• Collect minerals and develop your skills!
  
• Unlock new skills in order to get stronger!
  
• Wide variety of monsters and environments!
  
• The challenge level is high but not frustrating!
  
• Lots of Achievements to unlock!