Heracles

Heracles is a strange Warrior that used to reside in the Greenstone forest in the Boin Archipelago. He trained Usopp in the use of Pop Greens for two years.

Appearance
Heracles is dressed in a beetle-stylized armor that looks like a hero costume with a mask that covers his face and a mantle. He has a round shaped body with relatively thin arms and legs.

Personality
He has an odd habit of adding "n" to people's name (a Japanese quirk often done to show friendship), as well as at the end of sentences (in Japanese). For example, he called Usopp (ウソップ) "Usoppun" (ウソップン), and he himself is Heraclesun (ヘラクレスン). He also has a habit of repeatedly introducing himself. Heracles has a usual laid-back attitude, but is quick to react when he senses dangers and seems to care for Usopp's well-being, having saved him from being eaten multiple times.

Abilities and Powers
Heracles' main style of combat involves the usage of a spear and explosives. His attacks are apparently very fast. Though round in appearance, he is fit and strong which is evident from the way he defeated a giant beetle and man eating plant with a single kick. He also has a great amount of knowledge about the different plants and animals of the island where he lives and his armor gives him additional defence. He keeps a stock of Pop Greens in his belt. He also seems to be able to control giant beetles.

Straw Hat Separation Adventure: Boin Archipelago
Usopp encounters Heracles on the Boin Archipelago, where he was sent flying by Bartholomew Kuma. Heracles rescues Usopp from a giant beetle. Usopp, though thankful of Heracles, looks in shock at his proposal to eat the giant beetle. While Usopp is distracted, a giant man-eating plant tries to devour him, but he is saved once again by Heracles. Heracles informs Usopp to be more careful if he wants to keep his life and possessions. Heracles is later seen alongside Usopp eating ramen in a part of the large forest consisting entirely of edible food (such as "spaghetti plants", "ham fruits", and "chocolate rocks") while Usopp hungrily looks at the food around him, which led to the Straw Hat sniper to become fat, with Heracles emitting a gasp and looking at him in shock.

After the War
When a News Ku drops a newspaper down to the Archipelago, Usopp learns about the events of the Whitebeard War and tries desperately to get off the island to help his ailing friend and captain Monkey D. Luffy to get over the trauma of his brother's death. Heracles tries to stop Usopp from fighting a giant beetle, but fails as Usopp attempts to get past it. When Usopp lost, Heracles informs him that more and more dangerous creatures will appear as he tries to go away from the center of the island. But Usopp doesn't listen and takes off again regardless of Heracles' warnings. Heracles tells Usopp that escaping the island is impossible because of the giant creatures that get attracted to the aroma of the island; he notices that the island is beginning to move and warns Usopp to cling to something as due to the island is actually a large carnivorous plant called the Stomach Baron. The island moves again and Heracles saves Usopp from falling into the island's mouth.

Heracles then question Usopp for his sudden change of behavior since reading the newspaper, to which Usopp answers by saying that Luffy is in pain after losing his brother and that he needs to be there for Luffy. While Usopp was reading the article about Luffy going back to Marineford, Heracles asked him what he was reading now.

Some time later, Heracles and Usopp are escaping from the dangerous creatures on the island as they do everyday. Heracles realizes the hard determination Usopp gained after reading the newspaper, which makes him question what the pirate read. Usopp tells Heracles the message from Luffy and then he asked Heracles to train him, saying that he can learn a lot of things from Heracles, like fighting and sniping abilities calling him "Amazaing Warrior", "Sensei", and then remarking that his name is pretty cool. With all these comments Heracles gets excited and agrees to train Usopp, beginning with the different types of plants there are in the island and their different uses in battle, specifically Pop Green and their energy and growth properties. He trains Usopp in the use of Pop Greens for two years until the time has come for the latter to reunite with his crew mates.

Two Years Later
Heracles and Usopp escape the Boin Archipelago and travel to Sabaody Archipelago. As the Straw Hats prepare to set sail for Fishman Island, Heracles is shown commanding giant beetles to hold back the Marines from pursuing the Straw Hats. He wishes Usopp the best of luck.

Manga and Anime Difference
In the anime, it expands on Usopp's and Heracles' adventures on the Boin Archipelago, as well as bringing up facts that are not revealed in the manga until much later after the war.

The expansion of their escapade starts at Usopp is shown to be running away from a giant sunflower plant with Heracles watching on. Usopp asks Heracles to help him against the giant sunflower plant who is trying to eat him alive. Heracles manages to save Usopp and tells him to build up stamina as he is weaker than ants and worms on that island. Usopp denies this at first, but later agrees with Heracles when he sees a giant ant and worm. Heracles easily beats both the ant and the worm and asks Usopp if he wants to eat them. Usopp in his traditional fashion looks in utter disbelief at Heracles's proposal. He then informs Heracles that he is hungry and wants to eat something edible. Heracles takes him to a place where items like ramen, spaghetti, ham and chocolates are available in abundance. Usopp starts to gulp down the items and is told by Heracles to also work out to build stamina as eating alone won't do it.

Later Heracles loses sight of Usopp, who is busy eating out all the delicacies available on the island. When he finds him Usopp has already turned fat. He tells Usopp to lose some calories when all of a sudden the island starts to move and eats everything on it. Both Usopp and Heracles try to escape, with Heracles catching hold of a branch and tries to catch Usopp, but Usopp is too heavy for Heracles to hold on to. He waves his goodbyes to Usopp, believing it is inevitable that Usopp will be eaten. But Usopp catches a ramen branch and eats it to climb up and escape.

Later Heracles finds Usopp and tells him that fat things will definitely be eaten on the Boin Archipelago, which is in truth a group of giant carnivorous plants. He also informs him that it is impossible to escape the island.

Trivia

 * His name, "Heracles", comes from the Greek Hero Heracles, also known as Hercules in Roman mythology.
 * "Hercules" and "Kabuto" are both types of beetles and coincindentally represent both Heracles and Usopp respectatively (in Usopp's case it is his weapon).