Silpheed: The Lost Planet is a vertical-scrolling shooter presented at an oblique angle view. The plot takes place 31 years after the events of the first game, where most human colonies in the Solar System have been destroyed by an alien civilization named the UTOO. To prevent the UTOO from destroying the remaining colonies, as well as other celestial bodies within the universe, a squadron of starfighters known as Silpheeds are deployed to destroy the UTOO and restore peace to the universe.
The player controls one of these Silpheed ships throughout eight stages. The objective of each is to make it to the end by destroying formations of enemies and avoiding collision with them and their projectiles. At the beginning of a level, the player can customize their Silpheed with different types of weapons, including short-ranged bombs, a double shot, and a laser that pierces through enemies These weapons can be attached to either wing of the Silpheed, allowing for one side to have one weapon and the other side to have a different one. Brief “refueling” segments midway through levels allow players to swap their weapon types. Destroying enemies close to the player increases the score multiplier, referred to as “proximity scoring”, and increases the closer the player is to an enemy.
