Heka Heka no Mi

The Heka Heka no Mi ( ヘカテ ヘカテ ) is a Mythical Zoan type of Devil Fruit, in which the user is able to turn into a full or hybrid version of Hecate at will. Heka coming from Hecate or Hekate, in both Viz Manga, and the FUNimation dub called the Hecate-Hecate Fruit. This fruit was ate by Haku by after the fruit was put into affect his other brothers Baku and Taku were created or such, as a result of this fruit when it is active.

Strengths
The main strength of this fruit is that it gives the user a great boost in speed, strength and many other attributes. But the main strength in this is that, it allows the user to turn into Hecate much like the Daibustu Hito model. Not gaining much powers, but the user is able to have two completely other entities be with them in battle, this is how Haku was able to have his "brothers" after eating this fruit. It also was revealed to tell were Haku was in a hybird or full form, if he summons or such one brother he is a hybird and full being the second one.

Weakness
It would appear that even though the user is able to create two other entities, they do share on brain. So as such the user is in control of the other two and most of the times this can be a bit of a disadvantage. Other than that, the user will suffer the standard weakness of the devil fruit.