Myskina Acier

Myskina Acier is a character in the Heart of Gold special. He is Olga's father and a scientist who created the Pure Gold 200 years ago.

Appearance
200 years ago, Acier was a middle-aged man who had blonde hair that stuck up at all sides in the front and was gathered into a large bun in the back. He wore a scientist laboratory coat over a green shirt.

After spending 200 years living with dinosaurs, Acier became larger and decrepit, and his clothes were in tatters and his hair was very messy. He also wore a dinosaur suit in order to pretend to be one of the dinosaurs. However, after escaping from Bonbori, Acier developed a serum that returned him to his old appearance.

Personality
Acier is very loyal to his family, and went to great lengths to save his daughter Olga from a terminal illness, even though his wife died, which he was distraught about. After finding out that Olga was alive after 200 years, Acier wept with joy and assisted Monkey D. Luffy in his mission to rescue her from Mad Treasure, even planning to sacrifice himself for her at one point.

Like some other males, Acier is attracted to "cool things" such as the Franky Shogun. After escaping from Bonbori, Acier seems to have gained the persona of a mad scientist, gleefully testing experiments despite Olga's reservations.

Abilities and Powers
Acier is a brilliant scientist, capable of creating the Pure Gold, a substance that could effectively give anyone nearby immortality. Due to being in its presence in Bonbori's stomach, Acier stopped aging for 200 years, although now that he is separated from it, and unwilling to make it again, he will resume aging like normal. He also possesses enough building skill to construct a mine filled with traps and bombs in order to protect the Pure Gold. When he escaped from Bonbori, he successfully created a weight loss serum.

Due to being forced to act as a dinosaur for 200 years, Acier is capable of communicating with dinosaurs as well as the water lizards inside Bonbori's stomach.

However, Acier is physically frail, as he said that he would probably die if Luffy attacked him.

Past
200 years ago, Acier lived happily on Alchemi with his wife and daughter Olga, but Olga came down with the terminal and incurable South Blue Emperor Fever. Acier worked tirelessly to find a cure, which led to the invention of the Pure Gold, a substance which would stop Olga's aging and prevent the onset of the fever. Upon completion, Acier gave Olga a ring containing a little bit of Pure Gold, which caused her to be healthy again. However, the Pure Gold became recognized as a valuable substance, and Acier's wife was killed in a pirate attack. Olga, not knowing what the Pure Gold was for, blamed Acier for her mother's death and cast her ring into the sea. A giant fish named Bonbori then emerged and consumed the ring, and ended up consuming nearly the entire island of Alchemi, including Acier and Olga. Acier was separated from Olga, and thought that she had died. In order to avoid being eaten by the dinosaurs residing in Bonbori's stomach, Acier posed as one of them with a dinosaur costume, and lived with them for 200 years.

Heart of Gold
An adult dinosaur carried Monkey D. Luffy in its mouth to feed Acier and the young dinosaurs, but Luffy managed to escape and avoid being eaten. Acier was surprised to see another human for the first time in 200 years, and Luffy revealed that Olga had also been residing in Bonbori. Acier cried tears of joy to hear of his daughter being alive, and joined Luffy in his mission to rescue her from Mad Treasure. The two started building a boat to traverse Bonbori's stomach, but Luffy discovered a water lizard they could ride. Acier accidentally tamed it by making a smug face and causing it to laugh, and he and Luffy rode on the lizard, which Luffy named Chavez.

The duo crossed into Bonbori's second stomach, but the acids were now strong enough to harm Chavez's feet. As Acier tended to Chavez, Luffy confronted Psycho P and his army of men poorly disguised as Luffy's allies. Luffy saw through the ruse and attacked the enemies, but they suddenly turned into Acier, and Luffy was unable to distinguish who was the real one. Luffy had Acier make his smug face again to identify himself, and thus managed to take down the fake ones. Luffy then met his crewmates Roronoa Zoro, Sanji, and Franky as Acier outfitted Chavez to be able to make the journey, and he, Luffy, and Zoro rode toward Alchemi.

Acier, Luffy, Zoro, and Sanji arrived at Alchemi, and Luffy pulled him and Acier into the mine containing the Pure Gold as Zoro and Sanji fought the enemies outside. They caught up to Mad Treasure and his prisoners at the final gate, and Acier saw Olga for the first time in 200 years. He then opened a trapdoor under Olga and the Straw Hat Pirates, and confronted Mad Treasure alone, attempting to take the hunter down with him by blowing up the mine. However, Treasure captured Acier and took him outside where the Straw Hats and Olga were. As Luffy battled Treasure, Acier and Olga reconciled, and Luffy managed to defeat Treasure and send him flying into the wall of Bonbori's stomach. This gave Bonbori dry heaves, and Acier, Olga, and the Straw Hats rode the Thousand Sunny up Bonbori's throat as it vomited. They then watched as the Pure Gold became absorbed in Bonbori's lamp, and Acier stated that he would never make Pure Gold again.

Acier, Olga, Chavez, and Olga's steed Elizabeth departed from the Straw Hats on an island, and Tony Tony Chopper revealed that Olga's illness could now be cured as he cured her. Acier and Olga then resumed their life together, and Acier developed a serum that returned him to his old appearance, which he marketed as a weight loss product.