Exerion

 is a video game developed and published by Jaleco. It was released in arcades on February 1983 and licensed to Taito for manufacture and distribution of the game in North America. The player controls a starship and must fire at enemies on the screen while avoiding projectiles. The game uses a pseudo-3D scrolling background, giving a sense of depth, and the player's ship has a sense of inertia while it is being controlled with the joystick.
"Exerion" was ported to the MSX, Family Computer, and SG-1000. Two sequels were released.
Gameplay.
"Exerion" features parallax effects and inertia simulation. The player shoots formations of bizarre alien amoeba, egg-throwing birds and Pterosauric creatures, as well as UFOs while flying over the surface of a planet. The player has two types of guns: a slow double shot (unlimited) and a fast single shot (limited).
Reception.
In Japan, "Game Machine" listed "Exerion" as being the most popular arcade game in Japan in November 1983.
Legacy.
The Family Computer version of the game is included in the compilation "Jaleco Collection Vol. 1" for the PlayStation in 2003, as well as in the Game Boy Advance game "JaJaMaru Jr. Denshoki Jaleco Memorial", along with five other Jaleco Family Computer games. The original arcade version was later released for the PlayStation 4 as part of the "Arcade Archives" label on October 23, 2014 in Japan and on July 7, 2015 in North America and also on the Nintendo Switch in the Nintendo eShop by Hamster Corporation as part of the same series.
Two sequels to the game were released. "Exerion II: Zorni" was released for the MSX in 1984 alongside a port of the original arcade game. The second, "Exerizer", was released for arcades in 1987, which was released in North America by Nichibutsu under the title "Sky Fox". The player's ship, the Fighter EX, is a playable character in Jaleco's "Game Tengoku" series.