One Piece Devil Fruit Lamp - "Yami Yami No Mi, Dark Dark Fruit"
 
Here it is, the supposedly most powerful of all devil fruits - the Yami Yami No Mi. Blackbeard's power to create and control the darkness.
 
Okay, that sounds quite biblical, because after all we associate with the darkness first of all the "evil". Only as second we think then perhaps of the physical condition one connects with darkness namely the absence of light.
Marshall D. Teachs darkness Logia devil fruit erschäfft no demons but rather oriented to his physical model. And it is quite good at that. Just as darkness is said to be able to devour light, Blackbeard can devour and absorb anything with his power. Not least even the abilities of other devil fruit users. A real offensive and damaging power, such as the Fire or Magma Fruit, the Dark Fruit does not have. It simply "sucks up" everything in its way. Whether it's the things it absorbs like a black hole or the powers it blocks and absorbs from others, many Devil Fruit users look helpless against it. However, this also has the disadvantage for Blackbeard that he must constantly activate this power to be safe from other attacks, because unlike the rest of the Logias, he cannot transform into his element. Nevertheless, to obtain the Yami Yami, Blackbeard walked over corpses, murdered Thatch, the 4th commander of the Whitebeard Division, who had actually found the fruit and of which he was a member at the time, and fled away. Because the Dark Devil Fruit gives another very dangerous ability. With it, he can steal the devil's powers from killed people before their ability manifests itself again in a fruit somewhere. He gave himself the Gura Gura power, which once belonged to Whitebeard, and since then he has been on the way to "collect" devil powers and give them to his commanders.
Actually already quite evil.