Giygas

Giygas (ギーグ, Gyiyg), also called Giegue, is the main antagonist in the video games Mother and EarthBound, respectively. Known as the "Universal Cosmic Destroyer" or the "Embodiment of Evil", Giygas is an alien conqueror who wields an incredible psychic power, which would later be called PSI.

Giygas vastly differs between both games. In the first, he appears as a regular alien warlord and in the second he has become an unfathomable monstrosity of pure darkness with no body nor mind left. The reason between this drastic change of character is never fully explained. However, due to the far bigger impact it made on gamers, Giygas' character in EarthBound is much more well-known than his previous self, which is almost totally eclipsed.

Background
Giygas is an alien with huge psychic powers. In 1909, when Giygas was a small infant, other aliens of his kind abducted a human couple, George and Maria, who took a liking for him and raised him as their son. During this time, George studied the aliens' PSI powers without their permission, culminating with his escape back to Earth.

In the 80 following years, George spread the use of PSI over Earth, against the wishes of the Alien kind. Once he matured, Giygas was tasked by his people to remove PSI from Earth. However, Giygas still felt a strong attachment for his foster parents and particularly for Maria. In the end, he was forced to detach himself from Maria and begin preparations for the invasion of Earth.

Mother
In the course of the game, Giygas (known as Giegue in some translations) invades Earth with the ultimate goal to stop the spreading of PSI and take it back from mankind. Giygas uses his own immense PSI powers to spread his influence over Earth, swarming the world with his mind-controlling aliens henchmen.

In the process of his invasion, Giygas is eventually confronted by Ninten, the great-grandson of Maria and George and PSI wielder, and his companions.

Before the two can fight, Giygas offers Ninten to come with him to his home planet, implying that what he really wants the most is companionship. Ninten declines this offer though, as he enjoys his life on Earth, and Giygas is forced to attack.

During the course of the battle Giygas unleashes powerful yet undefinable PSI attacks and can only be defeated by using a song that Ninten learnt from Maria, which she used to sing to Giygas. The song triggers memories of his happy childhood in Giygas, who admits defeat and leaves, telling Ninten that they will meet again.

Between the games' storylines
After the events in Mother, Giygas was left to grieve both his foster parents and his failure and he eventually yet unexplainedly gained incredible dark powers. These powers were so huge that they destroyed his body and mind, leaving only a virtually all-powerful being of pure darkness and evil.

In this form, Giygas is incapable of coherent speech or thought, and is unable to control his might. His appearance alone cannot be defined nor even concieved by a human mind, should it wield the Power of the Earth, and his existence is beyond rationalisation. This makes Giygas very similar to Howard Phillips Lovecraft's Outer Gods, and especially Azathoth, the all-powerful but mindless "Sultan of Daemons." Giygas' essence manifests as a chaotic, bizarre darkness with no beginning or end in sight. He himself appears as a swirling reddish blur which somehow evokes a twisted, screaming face, and keeps warping and distorting himself.

Giygas now manifests as what can only be described as pure evil; in Porky Minch's words, "he is the Evil Power". Due to the loss of his mind, Giygas has become completely irrational. Porky attests that Giygas isn't aware of himself nor what he is doing, referring to him as "an all-mighty idiot". Giygas's power is no longer limitated to PSI and he gains complete control over darkness, dark magic and everything evil, raising a huge army of monsters and malevolent aliens, including the cybernetic kind called the Starmen.

EarthBound
Giygas returns to Earth many years later in the game EarthBound/Mother 2.

Now wielding a vast cosmic power which he is unable to control, Giygas becomes a threat to the existence of the universe itself. In an apocalyptic future set ten years after the beginning of EarthBound, Giygas rules the entire universe, which he engulfed in absolute darkness and reduced to ruins, wiping out nearly every living being. Fortunately, an insectoid alien named Buzz Buzz manages to escape and travels back in time to warn people of the impending catastrophe.

Ness, the game's primary protagonist finds the meteor in which Buzz Buzz has arrived in his era, learning about the evil of Giygas and that he is one of the only four people able to take him down, before having to fight one of the demon's creatures who followed Buzz Buzz. Ness is given the Sound Stone and instructed to record the Eight Melodies, in order to gain the power of the Earth and become strong enough to face Giygas.

In Ness' present-days, Giygas' evil influence quickly starts to spread all over Earth, corrupting both living beings and inanimate things. This leads to the creation of the Happy Happyists cult and the apparition of many monsters under the command of Giygas that Ness and his comrades have to fight. Giygas' influence corrupts Geldegarde Montoli, the mayor of Ness' town and turns Ness' bratty and obnoxious neighbour Porky (Pokey) Minch into a downright malevolent criminal mastermind who sets out to gain profit from Giygas' unlimited might. Porky eventually travels back further into time to meet with Giygas, whom he places into a device called the Devil's Machine, able to contain and control his tremendous dark power.

The protagonists eventually gain the Power of the Earth and reach Giygas' time a few months ago. They enter his hideout, where Porky confronts them inside a spider-like battle robot, having been appointed as Giygas' general. They defeat Porky, but Porky shuts the machine off in retaliation, unleashing Giygas in all his might. Ness and his three companions must then engage the extremely disturbing and nerve-wracking final battle of the game.

The battle against Giygas is very long and difficult. He uses random and unintelligible attacks, while babbling erratic and meaningless speeches, and no attack can harm him for real. He overwhelms the heroes until Paula calls out to the people of the Earth to pray.

Every time they do, Giygas gets hurt and turns into a new form containing many times his first form. The combined prayers reach Giygas and exploit his weakness, which similarly to the previous game turns out to be human emotions. What Giygas has become is then destroyed for good and fades into nothingness, erasing his apocalyptic future.

It's worth nothing to note that even after becoming this undefinable, mindless Dark Form Giygas somehow retains his fondness for human emotions. The fact that he repeats Ness' name and words such as "I'm happy" in his incoherent babbling refers to his desire for companionship and his offer to become friend with Ninten in Mother.

Interpretations
Shigesato Itoi has stated that his inspiration for Giygas' speech - but not the inspiration for Giygas himself - in EarthBound came from a traumatic childhood experience where he accidentally walked into an adult movie theater and caught a glimpse of a rape scene in the 1957 film "The Military Policeman and the Dismembered Beauty" (憲兵とバラバラ死美人 "Kenpei to Barabara Shibijin"). In actuality there was no rape scene in this film, instead a murder scene. As Itoi was a child at the time, he has stated his lasting memory of this experience is fuzzy at best.

Trivia

 * There is some speculation within the Mother community that Giygas was originally intended to return in Mother 3 as an unused boss character after the battle with the Masked Man.
 * PSI Brainshock is effective against Giygas, although only during a few of his various different stages.
 * Giygas is one of the three characters in MOTHER 2 who can use PSI Rockin (Love in japanese), along with Ness and Ness's Nightmare.
 * Gigyas' first form is a giant eyeball-like window in the Devil's Machine with Ness' face in the center. His second and third forms are undulating red swirls that resemble a screaming face if looked at the right way. In his final form, it is still an undulating red swirl (with the "screaming face" still visible). His form with the Ness-like face may be Ninten's as he wanted to be his friend.
 * It could be possible that Giygas' race had the ability to mix and match different PSI attacks to form 'patchwork' PSI. As these special PSI are made up of different PSI, it is impossible to see what the PSI was supposed to be like. One example is when Giygas used a multiple PSI Freeze attack on Ness' party, even though PSI Freeze is meant to target only one target.
 * In Mother 1+2, it is actually possible to defeat Giygas outside of the scripting by poisoning him. Doing so earns no exp and the ending proceeds normally.
 * There is a theory, that Giygas resembles a fetus. However, Shigesato Itoi said this theory is wrong. Howewer, some players still believe in it.
 * Some fans speculate that in Mother 3 Giygas was somehow used by Porky to control the Masked Man.
 * Giygas' form in Mother looks very similar to Mewtwo from the Pokémon series. It is possible that Mewtwo is based on his design. This theory is backed up by the fact that many of the people who worked on Mother later worked on Pokémon.
 * The static and fade out after Giygas is defeated resembles a television being shut off.
 * In the original SNES version, after you defeat Giygas, there is a glitch where the Shattered Man is still in the top floor of the museum in Summers. If you let it defeat you, the screen will be black, and nothing can be done. This is because after Giygas is defeated, all the enemies disappear, for some reason not the Shattered Man. This glitch is fixed in the Mother 1+2 remake for the GBA. Notice if that was fixed in the Wii U version too.
 * In The Frollo Show, Wilford Brimley has a diabeetus like powers and appearance called Wilfyias, which is definitely a parody of Giygas.