Majora is the main antagonist in Majora's Mask, and is also the one responsible for many of the troubles plaguing Termina's citizens.
The tale of Majora's Mask is surrounded by many mysteries. It is said that there was a tribe that had this mask in their possession and only "they" understood the powers of the mask. The mask's power it is said to have caused lots of trouble for this tribe that had this mask, and the tribe knew that the powers of Majora's mask could cause a great catastrophe, a catastrophe that is even beyond believing. However this tribe greatly feared of the possible catastrophe, they sealed Majora's Mask away to prevent the mask's misuse and to hopefully prevent the great catastrophe, unfortunately the tribe existed a very, very long time and eventually died off, and since they kept the information regarding the powers and legends of Majora's Mask a secret, that today's people do not understand the power of Majora's Mask, and somehow, very recently that Majora's Mask resurfaced. As the Happy Mask Salesman obtained the mask somehow, he also somehow discovered the mask's story, and he knew that the mask could not be misused. Unfortunately, the Skull Kid played a trick on the Happy Mask Salesman, causing him to lose consciousness, and the Skull Kid searched the Salesman bag for anything interesting, and pulls out Majora's Mask, having no knowledge of the mask, puts the mask on, and with that Majora's Mask takes over the Skull Kid, and before the Skull Kid met Link for the first time since Link defeated Ganondorf, the Skull Kid had used the Mask's power to cause Termina's moon to fall, this well could be catastrophe that the ancient tribe had feared that Majora's mask is capable of doing.
 Majora (Boss)
The first is Majora's Mask, basically it is just a floating mask that shoots out energy beams and will occasionally use a spinning attack upon you.
The second form is Majora's Incarnation which in my mind is kind of like a chicken to me where he will run around blazing out multiple attacks.
BEWARE:Majora's Incarnation is very fast.
And Finally there is Majora's Wrath taking on a more human form Majora will use many whipping attacks and has many attributes of it's previous to forms.
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