Pretty simple theory, but we know from Volume 1000 /Volume Z that Borsalino and Sakazuki joined the marines at the same time. (This information is non-canon, but I wouldn't be surprised if it was the case in the manga itself).
Sakazuki seems to be familiar with Dragon, and the two of them are also the exact same age.
It's very likely that Dragon was either an ex marine or some sort of Government agent, and he likely joined around the same time as Borsalino and Sakazuki too. Considering their talent and power, I can see them being "Marine Supernovas" basically and grouping together.
They were probably a trio like Garp, Sengoku and Tsuru. The reason I'm excluding Kuzan is because he's 7 years younger than Dragon/Sakazuki and 9 years younger than Borsalino, I feel like he joined at a much later date.
If this theory is true, I can see one of the reasons Dragon started the Revolutionary Army being that he was horrified by Sakazuki slaughtering people or something, idk.
Also, Borsalino seems to have some sort of connection to Vegapunk, who experimented on Dragon's former right-hand, Kuma.
Sakazuki seems to be familiar with Dragon, and the two of them are also the exact same age.
It's very likely that Dragon was either an ex marine or some sort of Government agent, and he likely joined around the same time as Borsalino and Sakazuki too. Considering their talent and power, I can see them being "Marine Supernovas" basically and grouping together.
They were probably a trio like Garp, Sengoku and Tsuru. The reason I'm excluding Kuzan is because he's 7 years younger than Dragon/Sakazuki and 9 years younger than Borsalino, I feel like he joined at a much later date.
If this theory is true, I can see one of the reasons Dragon started the Revolutionary Army being that he was horrified by Sakazuki slaughtering people or something, idk.
Also, Borsalino seems to have some sort of connection to Vegapunk, who experimented on Dragon's former right-hand, Kuma.