Cave Story is a freeware platform-adventure video game released in 2004 for PC. It was developed, designed, and programmed over five years by Daisuke Amaya, art-name Pixel, in his free time. The game features classic 2D platform mechanics and is intended as an homage to the classic games that Pixel played in his youth, such as Metroid and Castlevania.
The game focuses on an amnesiac silent protagonist who awakens in a cave. Through his explorations, he discovers a plot by the Doctor, a megalomaniac who intends to force the inhabitants of the cave to fight for him in his bid to conquer the world. The protagonist is thrust into the position of savior as he endeavours to defeat the Doctor.
The player progresses by jumping and navigating platform game puzzles and shooting enemies with the equipped weapon. The player collects multiple weapons over the course of the game and can quickly switch between them in combat. Defeating enemies sometimes yields bouncing yellow triangular objects that increase the weapon energy of the currently equipped weapon. Weapons can be improved up to level three, but taking damage causes weapons to lose energy and level down. Health and missile capacity upgrades are scattered throughout the game world.
Cave Story takes place within the cavernous interior of a floating island. The island is populated by Mimigas, a race of sentient, rabbit-like humanoids. A particular species of red flower that grows in the island causes the normally peaceful Mimigas to go into a vicious frenzy. The island also conceals an artifact called the Demon Crown, which has vast magical powers. A previous expedition to the floating island sought to harness the power of the red flowers and Demon Crown to use as a weapon for wars on the surface world.