Vegapunk

Doctor Vegapunk (Dr.ベガパンク, Dokutā Begapanku) is the leading scientist in the employment of the Marines. His work includes discovering the secrets and uses of Seastone, the secrets of how Devil Fruit powers work, and various other scientific achievements. He has a bodyguard named Sentoumaru and hails from the technologically advanced island of Karakuri.

Personality
Apparently, at least in his youth, he was a kind-hearted person who cared very much for the inhabitants of his island, willing to help them with his inventions. He was considered the island's pride and joy, and his friends are still hoping in his return.

Abilities and Powers
Vegapunk is a genius scientist whose scientific expertise is said to be at least 500 years ahead of his contemporaries. It seems that even in his youth the scientist was a genius, but lacked the skills and funds to develop his inventions.

Through his research he discovered ways of allowing Marine ships to pass through the Calm Belts without fear of Sea King attacks by covering the bottom of the ships with Seastone. He also discovered exactly how Devil Fruit powers are transferred over to a user, and was the scientist behind the method of adding Devil Fruit powers to inanimate objects.

He is the one who modified Bartholomew Kuma into a cyborg, and has produced many Pacifista replicas of him, granting them some of the abilities of Kizaru's Devil Fruit in the process. These replicas bleed actual blood, but lack Kuma's own Devil Fruit powers.

Scientific Achievements

 * Seastone usage
 * Restraining items (nets, handcuffs, stun batons/swords)
 * Covering the bottom of ships for avoiding Sea Kings
 * Devil Fruit research
 * What Devil Fruits really are
 * How devil fruits react with humans
 * Allowing objects to "eat" the fruit
 * Research into the Pika Pika no Mi
 * Pacifista project
 * Modifying Bartholomew Kuma into a cyborg
 * Creating cybernetic replicates of Kuma
 * Installing devices that have a similar ability as the Pika Pika no Mi to project explosive lasers
 * Other
 * Climate Control (unfinished)

Trivia

 * In relation to a question asked by a fan about how come Luffy's Devil Fruit was already in the Devil Fruit encyclopedia when he ate it, Oda hinted that Vegapunk might know what Devil Fruits really are.
 * Vegapunk is comparable to Leonardo da Vinci, who is often thought of in modern history as a man who was ahead of his time. Some historians also go so far to say Leonardo was more than 5 centuries ahead of his time, just as Vegapunk is likewise considered 500 years ahead of his time.
 * Despite Vegapunk's achievements, he has yet to make a personal appearance in the series.