Sagaia, also known as Darius II, is a side-scrolling shooter game that was released for the Sega Genesis in 1990. It's part of the Darius series, known for its unique aquatic-themed robotic enemies and branching level paths. Players take control of a spaceship tasked with defending Earth against an alien threat, navigating through various stages and facing multiple challenging bosses. The game is known for its difficulty, memorable soundtrack, and two-player cooperative gameplay.