Here you will find extra info on topics that may need elaboration.
The Chimera Theory
Question: How was Blackbeard able to obtain a second devil fruit power?
Theory: Blackbeard is genetically more than one person, a trait known as Chimerism.
1) Zoro and Luffy refer to Blackbeard as: “It’s not he… it’s they”.
2) Blackbeard’s pirate flag has 3 skulls.
3) Shanks wants revenge against Blackbeard for causing the beast-like scar on his left eye.
4) Marco the Phoenix mentions Blackbeard’s body is “atypical”.
1) Zoro and Luffy may have been referring to Blackbeard’s crew.
Blackbeard may actually have 3 devil fruits.
– Paramecia (Quake Fruit) [Canon]
– Logia (Darkness Fruit) [Canon]
– Zoan (???) [Speculation]