Ryu Nakanishi, designated G-5 and codenamed the Horned Owl, operates as the chief pilot for the Science Ninja Team’s mechanized arsenal, commanding vehicles like the God Phoenix, New God Phoenix, and Gatchaspartan. In the original series, the 17-year-old stands at 170 cm with a stocky 80 kg frame, blending muscular strength beneath a sumo-inspired physique. His casual wardrobe features a green-and-yellow shirt emblazoned with a bold "5" and khaki pants. The OVA reimagines him as a 25-year-old biracial Japanese-Aboriginal Australian, sporting a deep tan, a vibrant purple-and-blond mohawk ponytail, and surfer-inspired attire, reflecting his upbringing near Australia’s Great Barrier Reef. Raised in a coastal fishing village, Ryu joined the Science Ninja Team after saving Dr. Nambu from a boating accident at age 13, leveraging his maritime skills to secure his role. Relocated to Utoland City, he maintains a civilian cover as a yacht harbor manager, concealing the God Phoenix beneath the waters. His family—father Matsuzo and brother Seiji—remain integral to his life, distinguishing him as the sole team member with active familial connections. In combat, Ryu’s Bird Style suit evolves from a brown-and-green ensemble with a lavender visor in the original series to a deep green and gold OVA redesign. He employs raw power to grapple ships or crush foes with body slams. Armaments shift across missions: a harpoon gun, an elastic adhesive Gripper in *Gatchaman II*, and the Owl Sickle—a kusarigama—in *Gatchaman Fighter*. His Tornado Fighter technique merges with teammates to unleash devastating cyclones. Despite his role as the team’s lighthearted jester, often paired with Jinpei, Ryu balances humor with steadfast loyalty. His easygoing demeanor masks physical resilience and occasional irritability when provoked. Off-duty, he dozes at the quiet harbor, his mundane cover contrasting sharply with high-stakes missions. As a pilot, he maneuvers specialized mecha like the amphibious Horned Tank (*Gatchaman II*) and the bulldozer-derived Gatcha Five (*Gatchaman Fighter*), which anchors the Gatchaspartan’s rear. Unrealized designs from the cancelled Imagi film varied from armored bulk to sleeker forms, all retaining green-and-gold motifs. Spin-off appearances in *Yatterman* and *Time Bokan: Royal Revival* feature him in background cameos, echoing his original design and underscoring his role as a steadfast, if less flashy, cornerstone of the team’s operations.