Exerion

Exerion is a vertical shoot 'em up published by Jaleco in 1983 and licensed to Taito for distribution in the US. Screenshot from the arcade version Exerion is a shoot 'em up game with parallax effects and inertial simulation, which is remarkable for 1983. The player travels through strange scenarios and shoots at aliens. The player has two types of weapons: fast single shots (limited) or slow double shots (unlimited). In 1984, along with the MSX1 port of the original, a sequel titled Exerion II: Zorni was released for the MSX1, with similar gameplay to the original. There were also plans for an NES version of this game. In 1987, the semi-sequel followed with the title Exerizer, also known as Sky Fox.