Oystron is a single-player action and shooter game in which the player controls a ship using a joystick, firing at enemies and collecting pearls dropped by space oysters. In this game, the player's ship appears on the left side of the screen while enemies attack from the right, and the player must shoot oysters to reveal pearls, then collect them and bring them to a designated zone. The game features a storyline set in a sci-fi universe where players defend their pearls from enemies and bosses, with each level culminating in a boss fight against a creature called Oystron. It stands out with its unique gameplay mechanics involving pearl collection, boss battles, and a warp phase where players must avoid enemies at high speed, along with themes of space combat and resource collection.