Appearance: His trademark features are his spiky white and green hair and the "cracks" (petrification scars) remaining on his forehead from when he was revived. Character Appeal: A thorough rationalist with a passionate heart. While he appears to be a cool-headed, logical realist, he is a deeply compassionate man who never abandons his comrades. Indomitable Spirit: He possesses superhuman mental strength, having counted every second while petrified to maintain consciousness. Roadmap Strategy: No matter how advanced the modern convenience (antibiotics, cell phones, cars, etc.), he excels at creating "roadmaps" to build them step-by-step from available raw materials using modern scientific knowledge.

The "World's Most Covetous Man." A stoic hard worker who never compromises on his own desires. His greed became a major driving force for restarting the stagnant economy and civilization, such as creating a new currency (Dragos) in the Stone World. Genius Navigation Skills: Having sailed sailboats since middle school, his "sailor's intuition" for reading the wind and weather by skin feel boasts 10,000,000,000% accuracy. High Leadership and Magnanimity: Though he appears arrogant and haughty, he is an excellent commander who evaluates others' talents more fairly than anyone and puts the right people in the right places. He also has a gentlemanly side, affirming that all women are beautiful in their own unique way.

Self-taught Scientific Inquiry: Since childhood, he collected minerals—an act forbidden by village laws—and discovered principles like flame tests and soap bubbles on his own. Bond with Senku: By combining Senku's knowledge (the power of past civilization) with Chrome's knowledge (knowledge of materials sleeping in nature), the Kingdom of Science develops significantly. Caring for Comrades: He has grown into a fine sorcerer (scientist) with a passionate heart, willing to risk his life to save his friends. He is in love with Kohaku's older sister, Ruri.

Appearance: Half of his hair is white, and he has a large, mouth-like petrification scar on his left cheek. Role and Appeal: Initially revived by Tsukasa Shishio, leader of the Empire of Might, as a spy to confirm Senku's death. However, moved by Senku's overwhelming scientific prowess, passion, and the modest bribe of a single bottle of cola, he defects to the Kingdom of Science. He pretends to be a self-centered egoist who only sides with whoever benefits him, but his true nature is very compassionate and loyal to his friends. Everyone calls him "Gen."

Non-killing Conviction: He holds a strong belief, saying, "I just don't want anyone in front of me to die." He is a pacifist who values life—friend or foe—rather than a cold rationalist. From the Tsukasa Empire to the Kingdom of Science: Early in the story, he appeared as the No. 3 (one of the Three Generals) of the Tsukasa Empire. However, resonating with Senku's goal of "letting no one die," he secretly communicated with and eventually joined Senku's side.