Vaati

Vaati is the main villain of The Legend of Zelda: Four Swords and its following titles. He mainly appears as a black orb with a single eye and bat-like wings. Vaati was originally a light purple Minish, and in this form, he has light purple hair and red eyes, one of them being obscured by his hair.

The Legend of Zelda: Four Swords
In The Legend of Zelda: Four Swords, the game starts with Princess Zelda sensing the seal containing Vaati within the Four Sword weaken. She and Link go to the Four Sword Sanctuary to check on the seal. Vaati manages to escape, and he captures Zelda with the intent of forcefully making her his bride. As Vaati makes his escape to his palace, Link gets knocked out. After recovering, Link takes the Four Sword goes on a journey to rescue Zelda and defeat Vaati.

Vaati is the final boss. After being defeated in the final battle, Vaati is sealed within the Four Sword, and Zelda is rescued.

The Legend of Zelda: Four Swords Adventures
In The Legend of Zelda: Four Swords Adventures, Dark Link tricks Link into releasing Vaati. Dark Link ambushes the shrine maidens while they are visiting the enshrined Four Sword and seals them all within magical crystals which he took with him, similar to events in The Legend of Zelda: A Link to the Past. When Link draws the Four Sword to battle Dark Link, Vaati breaks the seal and escapes.

In a twist ending, is revealed that Vaati was being used by Ganon. Vaati is the penultimate boss, and Link fights him before facing off against Ganon. Instead of sealing Vaati into the Four Sword, Link manages to defeat him entirely.

The Legend of Zelda: The Minish Cap
In The Legend of Zelda: The Minish Cap, set before the events of the previous two The Legend of Zelda: Four Swords titles, Vaati is a young sorcerer wielding powerful dark magic. Early in the game, Vaati wins the annual swordfighting contest at the Picori Festival, and the reward for doing so is being allowed to touch the sacred Picori Blade, which would later become the Four Sword. When the Bound Chest is brought before Vaati, he breaks the seal on the chest, releasing several monsters upon Hyrule. Vaati recognizes the mystic aura protecting Zelda, so he turns Zelda to stone so that she cannot interfere with his plans. Upon looking into the chest, Vaati does not find the Light Force within, so he leaves to search for it elsewhere in Hyrule. Throughout Link's adventure, Vaati usually emits a sinister laugh before confronting Link.

Later, it is revealed that Vaati was originally a Minish who served as Ezlo's apprentice. One day, when Ezlo was not looking, Vaati put on the Mage's Cap, created by his former master Ezlo, without permission and wished to become a powerful sorcerer. Vaati became corrupted by wickedness in the hearts of men, and his lust for power continued to grow. Vaati placed a curse on Ezlo that transformed him into a green tunic, and Vaati proclaimed himself to be the master over Ezlo.

While Link is collecting the Four Elements to infuse with the broken Four Sword, Vaati impersonates King Daltus and orders Hyrule's soldiers to try and find the Light Force. In the Elemental Sanctuary, after Link infuses all Four Elements into the Four Sword, he and Ezlo access a hidden room where they learn that the Light Force is located within Zelda. Still disguised as King Daltus, Vaati followed them into the room to also learn where the Light Force is located. He appears before both Link and Ezlo, and reveals his true form almost immediately afterward. He insincerely thanks them for revealing where the Light Force is. Vaati proceeds to kidnap Zelda, and he takes her to the roof of Hyrule Castle. Using his dark magic, Vaati warps the castle into becoming Dark Hyrule Castle.

By the time Link goes onto the roof of the castle, Vaati managed to steal most of the Light Force within Zelda, and with its power, Vaati transforms himself into a more powerful being, Vaati Reborn. During the final battle, this is the first form that Link fights. Vaati then assumes his next form, Vaati Transfigured, beginning the second phase of the battle. After defeating Vaati Transfigured, Link and Ezlo heal Zelda, and the three of them make their escape to Hyrule Castle Garden. When this happens, Link is transported to a dark arena where he battles Vaati's strongest form, Vaati's Wrath. After a long battle, Link defeats Vaati and seals him away into the Four Sword once more.

Quotes

 * "Vile? I am a sorcerer now, and my power is beyond compare! None can stop me..."
 * "This year, on the day that comes but once a century, the portal opens. And when it does, I shall claim the Light Force as my own. I will be transformed, perfect, and there will be none who can stop me..."
 * "Heh heh heh... To think things would go this well! The Picori Blade and the Bound Chest spoken of in Hylian lore... This chest must hold that which I seek! I'll relieve you of its contents now."
 * "Mmmm ah hah hah hah! Do not interfere with me... As victor, I've earned the right to approach the Picori Blade... I've been waiting for this moment!"
 * "The princess who holds the power of light... That mysterious power is said to flow in the veins of every royal lady in your family ever since that day when it was gifted to your people. If I leave you now, you'll only cause me trouble later. That will never do. To stone with you!"
 * "Heh heh heh heh... All who stand in my way shall share this fate!"
 * "Interesting. You're the last person I expected to find here. And just as I was wondering who could be behind this, I find my old master..."
 * "And, as always, you are dressed in...heh heh heh...the shabbiest of rags. My curses are not to be mocked. The one I cast on you is most powerful. No matter what power you wield, you will never break it."
 * "Fool! A hat that grants the wishes of its wearer is a spectacular creation! Thanks to you, I have gone from being a meek, miniscule nothing to...the greatest sorcerer alive!"
 * "Ha ha ha! You ARE persistent, aren't you?"
 * "Heh heh heh heh heh heh... So, you've come to stop my little ceremony. Well, you're too late. A mere three more chimes of the bell will bring the ceremony to its end! And with the third toll of the bell, I will become like a god! And your precious Princess Zelda will be nothing more than cold, dead stone."
 * "But let me first attend to the pesky worms who would trifle with me..."
 * "I will have no more of you interfering with all of my plans! Let me show you true power!!"
 * "Well, you seem to have some fight in you. I commend your bravery. But you will not survive...THIS!!"
 * "Grrrrr..... I am filled with a power that you cannot begin to understand! Do you think that puny sword will save you from ME?!"
 * "What... What is this madness? I have the power of a god! I have unstoppable might!!! How could I lose to a child?!?"
 * "Heh heh heh heh... You will not escape, boy. Now, you will see the true power of the Light Force... For I have become Vaati, the master of this world!"
 * "Fool! I... But the Light Force... My power... I had such power..."

Trivia

 * In Nintendo Power's 210th issue, Vaati was listed as number two of the top five The Legend of Zelda series bosses, surpassed only by Ganon himself.