Giygas

Giygas (Japanese: ギーグ Gyiyg), also known as Giegue in, is the main antagonist in Mother and EarthBound. Giygas was raised from infancy by a woman named Maria and her husband George, both of whom were abducted from Earth in 1909. During this time, George studied the aliens' PSI powers without their permission, culminating with his escape back to Earth.

In
Known as Giegue, Giygas invades Earth, abducting parents and sending other aliens and robots to attack people, especially Ninten. His first attempt was to have Ninten's lamp assassinate him, but this failed attempt leads Ninten to start his journey, discovering who Giygas is, and what relation he had to his family. Atop Mt. Itoi, Giygas is confronted by Ninten and his companions. Before the fight actually begins, Giygas seems to offer to spare Ninten's life, asking him to come with him back to his planet. Ninten declines, and after being turned down, Giygas attacks him, and is invulnerable to every attack. After Ninten and his friends sing the Eight Melodies multiple times, Giygas is forced to retreat as the emotional stress becomes too much for him to handle, not before promising to return and try again.

In EarthBound
In EarthBound, he has ruled the world ten years into the future, and uses the Apple of Enlightenment to see further into the future. Giygas witnesses his defeat at the hands of Ness and his party, and sets out to prevent this from happening. Ness hears about him from Buzz Buzz, who came from the future to warn him about Giygas' plot. Shortly afterwards, they are both attacked by one of Giygas' henchmen, a Starman Jr..

Ness goes through all of Eagleland to harness his powers in order to defeat Giygas, and gains three fated companions - Paula, Jeff, and Poo - along the way. Giygas must be fought in the past, and to go there, the Phase Distorter must be used. The third one brings the party to him, with them becoming robots in the process. When finally defeated, the game will end.