Goeis (commonly referred to as Butterflys), are one of the main fighters of the Galaga Legion. Designed as being more adaptive than their Zako counterparts, these fighters are often used to act as the guards of Boss Galaga ships. Their appearance resembles that of a slightly alter Earth-Butterfly.
Goei are an average Galaxian fighter with moderate armor and significantly damaging attacks. They fly at a medium speed like Zako, but tend to adapt better with their surroundings, being able to target an enemy even if they manage to avoid danger. They are the preferred fighter chosen to act as bodyguards to Galagon fighters. Like Zako, they have been used often in attacks on the Solar System, with the exception of the UIMS conflict. They tend to fire two shots in case one of them fails to hit enemy targets. As with their Bee-counterparts, they have a pair of wing-like solar panels.