Gabiru begins as prince of the lizardmen tribe dwelling in the marshes of the Great Jura Forest. As the sole named warrior among his people initially, he exhibited pronounced arrogance and overconfidence, convinced of his superiority due to his status. He deeply respected his father, Chief Abiru, though expressed annoyance when not addressed by his bestowed name, inheriting traits like bravery and loyalty to his kinsmen. His inflated ego, however, made him vulnerable to manipulation. Spurred by subordinate flattery and Gelmud's schemes, Gabiru launched a rebellion against his father during the Orc Lord crisis, aiming to lead the lizardmen independently. This act proved catastrophic, endangering his tribe and exposing Gelmud's exploitation. Accepting full responsibility, Gabiru faced exile as punishment, though many loyal followers and his sister Souka chose to join him. After exile, Gabiru and his group sought sanctuary within Rimuru Tempest's growing Jura-Tempest Federation. Rimuru granted them refuge, offering Gabiru a second chance. Receiving a new name from Rimuru triggered an evolution for Gabiru and his followers, transforming them from lizardmen into dragonewts. This metamorphosis altered Gabiru's physique: his scales shifted from greenish-black to purple, he sprouted dragon-like wings and larger horns, and his scales hardened. Later, following Rimuru's evolution into a True Demon Lord during the Harvest Festival, Gabiru underwent a further transformation. His scales took on a reddish hue, magnificent horns grew from his temples, and he attained the title "Heavenly Dragon King". Gabiru's personality underwent substantial change after exile and joining Tempest. Humbled by his failures, his ego diminished considerably. He grew more level-headed, open-minded, and respectful towards others irrespective of race or status. While retaining some eccentric quirks and occasional flamboyant enthusiasm, these became viewed as endearing traits. He developed profound loyalty to Rimuru and dedicated himself to the Federation's prosperity. He also forged a strong friendship with Vesta, collaborating on research and development. Within the Jura-Tempest Federation, Gabiru assumed multiple key roles. He became captain of the Hiryuu, the nation's primary aerial attack force, commanding dragonewts and wyverns as part of the Third Corps. His leadership skills, once hindered by arrogance, flourished. He also played a vital role in the research department alongside Vesta, contributing significantly to the mass production of Hippokute herbs and healing potions. His importance earned him appointment as one of Rimuru's Twelve Guardian Lords. Furthermore, he held a position among Rimuru's key executives. Gabiru's combat abilities grew substantially. Initially a capable but inexperienced warrior, his evolution into a dragonewt granted flight and new powers. He wielded the legendary Vortex Spear inherited from his father. His Unique Skill, initially "Showoff" (Midasmono), allowed altering destiny once daily. After his awakening as a True Dragonewt and Heavenly Dragon King, this evolved into the Ultimate Gift "King of Moods" (Mood Maker). This potent ability granted accelerated thought processing, fate manipulation, control over unexpected events, spatial manipulation, and deployment of multiple barriers. He also gained the Dragon Warrior Form (Dragon Body), enhancing attack, defense, and regenerative capabilities, plus the ability to absorb magic and construct armor. His power level reached Special A rank after Rimuru's Harvest Festival, and his combat potential increased significantly when wielding the Vortex Spear.