Zemus

Zemus is the true main antagonist of Final Fantasy IV behind Golbez's plot in Final Fantasy IV. Wishing to destroy the planet, he is the master of the four archfiends, corrupts Golbez, and through him, controls Kain and commands Cecil's former position of Captain of the Red Wings to carry out his will to take the Crystals. 
==History==
===Final Fantasy IV===
Zemus is a member of the Lunarian race, who came to the Blue Planet (the planet where the Overworld and Underworld exist on) to coexist after losing their own. The Lunarians found humanity to be too far behind to coexist with, and decided to rest in stasis until humanity was ready. However, Zemus refused to rest and wanted to instead kill all life to make room for the Lunarians. Zemus was eventually forced into stasis, but his evil was able to corrupt Golbez due to his part-Lunarian heritage and use him for his goal.
Zemus' plan was to awaken the Giant of Babil to destroy the planet, which required the 4 crystals of light and the 4 crystals of dark. To do this he had the king of Baron murdered and replaced by Cagnazzo, who ordered the Red Wings to pillage Mysidia and take their crystal, making Golbez's presence known in order to command the Red Wings after Cecil was believed dead after using him to unknowingly destroy the village of Mist with the Carnelian Signet.
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The Red Wings then invade and bomb Damcyan to take the second crystal of light, leaving of its inhabitants dead except for prince Edward Chris von Muir, who was protected by his parents and Anna. 
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At some point, with the assistance of Dr. Lugae, they invade Edge's kingdom, seemingly giving Lugae free reign over turning the corpses of Edge's parents into demonic monsters, an act that disgusts the fair-dealing Rubicante.
Fabul's crystal of light is taken after the kingdom's forces were overwhelmed and Golbez defeats Cecil and the others. He kidnaps Rosa when she discovers the aftermath and later uses her to coerce Cecil to deliver the last crystal of light to him.
By the time Cecil and his party reach the Underworld, two crystals of dark were already taken, the third by a combination of using possessed dolls to spy on the Dwarf king and finding out where the chamber is, and either Golbez's body seemingly being reanimated after death or his still corrupted his soul and grabbing the crystal and leaving
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It isn't until Cecil finds Fusoya that he learns of Zemus, the Lunarians, and that Golbez is his brother. Fusoya then joins the party to aid them in destroying the giant as soon as it activates. After the giant is destroyed, Golbez comes to his senses and goes to kill Zemus in revenge, and is joined by Fusoya.
In Final Fantasy IV'
Also tools of Zemus are the Four Fiends of the Elements, who are merely followers of Zemus, not victims of his telepathic powers. After Kain restrains from killing Cecil, Golbez (being controlled by Zemus) sends the Four Fiends to do the dirty work of killing the heroes.
Zemus's final tool of evil is Dr. Lugae. Though it is never said whether Dr. Lugae is being controlled by Golbez or not, he is the self-proclaimed "brains behind Golbez's operation" who works in conjunction with the Fire Fiend Rubicant. Dr. Lugae is soon killed by the party in the Tower of Babil.
Cecil first learns of Zemus after meeting the Lunarian Fusoya on the moon. Fusoya reveals that Zemus plans to use the power of the Crystals to call forth the Giant of Babil, which will destroy all life on Earth. Cecil and Fusoya return to Earth in hopes of stopping the Giant's summoning. However, they return too late. They go inside of the Giant and destroy its core, as well as the Four Fiends. Golbez storms in enraged, but Fusoya uses his power to release Golbez from Zemus's control. This also ends Golbez's control over Kain.
When Golbez realizes what has happened, he and Fusoya return to the moon and kill Zemus using the White Meteo spell. Though Zemus dies, the evil inside of him takes a physical form, Zeromus. Golbez and Fusoya attempt to use the White Meteo spell again, but to no avail. To weaken Zeromus's powers, Golbez tries to use the Crystal. However, the small amount of evil still inside Golbez's heart does not allow the Crystal to work. Cecil, pure of heart, then uses the Crystal and defeats Zeromus, returning peace to the world.
Category:Antagonists
Category:Lunarians
Category:Final Fantasy IV characters
Category:Final Fantasy IV bosses