We still know that, in One Piece, the enemies of the pirates are the marines. In particular, the Marine is commanded by 3 Admirals, who are in turn commanded by the Fleet Admiral; nowadays, the 3 Admirals are Kizaru, Fujitora and Ryukugyu, while the Fleet Admiral is Akainu.
There is, however, another person who is even more powerful and important than the Fleet Admiral: this is Kong. In fact, Kong is the World Government Commander-In-Chief: this means that he has the full control on the Marine, on the Shichibukai, on Enies Lobby and on the Cipher Pols; for this reason, he’s said to be second only to the Gorosei.
But what kind of power can a man like this own?
We don’t have any specific information about his abilities, but we know that, during Gol D. Roger’s era, he was the Marine Fleet Admiral, so he’s supposed to be AT LEAST as powerful as his successor Sengoku; in addition, I have a theory based on his aesthetic features, let me introduce it to you!
Looking at him, I think that he can be easily compared to a kind of monkey, a gorilla more precisely; for this reason, I think that he might have the power of a mythical Zoan-type Devil Fruit. I don’t know what could be the name of this Devil Fruit, but I guess it would be related to Sun Wu Kong.
Wait, who is Sun Wu Kong?
Well, Sun Wu Kong is a gorilla protagonist of a Japanese legend; in this legend there are some coincidences with Kong’s life: apart from the two characters themselves which are homonyms, in the legend Sun Wu Kong fights against 4 dragons, which are the 4 emperors of the sea, while in One Piece he commands the Marine, which fights against the pirates, among who there are the 4 Yonko.
Moreover, in the legend Sun Wu Kong, who is also called “Sengoku”, meets Buddha, while in One Piece the character who has the ability to transform into a Buddha-like being is called Sengoku.
Another aesthetic feature to consider, in my opinion, is the fact that, in the legend, Sun Wu Kong usually wears a crown and, looking at Kong’s image, his hair can be considered as similar to a crown.
If the connection between Kong and Sun Wu Kong is true, then Kong may have the power to be invulnerable, since in the legend Sun Wu Kong’s skin can’t be injured by any kind of weapon; is also true that, in the image above, we can notice a scar under Kong’s left eye, but it can have been easily caused by Roger, since we don’t know yet his powers.
Of course, this is just a theory and it’s probable that we have to wait a very long time before discovering Kong’s real powers, but you don’t have to forget that, in Oda’s work, “coincidences” never exist; nothing is done for no reason.