The truth about Monkey D Luffy’s Devil Fruit is revealed in the latest "One Piece" 1044 by Gorosei in Mariejoa. 

As we all know, the mystery around the Devil Fruit and its capabilities are very much at large. Initially, the Devil Fruit consumed by Luffy was thought to be the Paramecia type, Gomu Gomu no Mi. 

Paramecia type is known to be the most common of all three types of Devil Fruits. It grants their users superhuman powers outside of transforming into an animal or elemental. It is known to alter the user’s physiques, objects and environment around them too. 

Gomu Gomu no Mi is known to give the user’s body properties of a rubber, making them a Rubber Human. 

In the latest chapter of "One Piece", Gorosei said that Luffy’s Devil Fruit is the Mythical Zoan Hito Hito no Mi: Nika instead of Gomu Gomu no Mi. 

Devil Fruit Zoan
Unlike Paramecia type, Zoan type allows the user to transform into an animal species at will. It’s first introduced by Dalton who transformed into a Bison. Zoan class Devil Fruit has three sub classes so far, that is the Ancient Zoan, Mythical Zoan and Artificial Zoan. 

Ancient Zoan is a subclass Zoan that allows users to transform into ancient animals such as dinosaurs and they are much rarer than the regular Zoans. Mythical Zoan allows the user to transform into creatures from myths and legends like phoenix, nine tailed fox (Kyubi no Kitsune) or the Yamata no Orochi. 

Artificial Zoan is a man made type of Zoan fruit, one of the examples is from the character Momonosuke who can transform into an Eastern dragon yet cannot control his powers.  

Awakening Luffy and his Devil Fruit
In "One Piece" 1044, Gorosei revealed that the World Government has been trying to grasp Hito Hito no Mi for the last 800 years but they failed every time. It is as if the Devil Fruit is trying to stay far away from them. In truth, what makes the Hito Hito no Mi different from the rest is that it has a mind of its own. 

Luffy feels like his Devil Fruit has reached Awakening thus revealing that it's his ultimate power, calling it the Gear 5th. The Straw Hat captain brutally drags Kaido up to the skies of Onigashima immediately. Later, Awakening Luffy shows its powers by transforming the ground to rubber and deflects Kaido’s Boro Breath.
 
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