Akumu Akumu no mi

The Akumu Akumu no Mi is a Paramecia-type Devil Fruit that allows its user to that allows the user to enter people's nightmares and to summon the person's nightmare and make it appear in the real world and transform it into a beast making the user a Nightmare Human (ナイトメアヒューマン  Naitomeahyūman). It was eaten by Erebus Soren captain of The Nightmare Pirates.

Appearance
The Akumu Akumu no Mi is a jet black fruit, it is the size and shape of a Carambola. The fruit has various ghost faces  on the inside.

Strengths and Weaknesses
The main strength of the Akumu Akumu no Mi is to summon and control the embodiment of people's nightmares. They can summon the physical form of nightmares and bad dreams and can control them to their will. The user can enter people's nightmares and to summon the person's nightmare and transform the nightmare into a different type of beast like an animal or something deform and monstrous. By summoning a person's nightmares and the user can give them shape, (which Erebus Soren refers to as "Nightmare beast").The user can make the fear a fire (Pyrophobia) into a different animal like a horse and the animal gains pyrokinetic powers.

The user make lose control of the Nightmare beast as they are filled with evil intent but as long as the user as a strong enough willpower they can over power them. Other than that there are no weakness aside from the standard Devil Fruit weaknesses.