Shun Kazami co-founded the Battle Brawlers and co-created the Bakugan game with Dan Kuso. Once the world's top brawler, he dropped to sixth place after Masquerade dominated the rankings. Living with his grandfather, a former ninja warrior, Shun received ninja training and valued independence, often operating alone. His mother's illness and subsequent death deeply affected him, leading to a temporary retirement from brawling until he rejoined to fight Masquerade; the exact circumstances of her death differ between Japanese and English versions. Calm, reserved, and analytical, Shun rarely displayed emotion, even under pressure. He approached brawling with strategic precision, blending ninja tactics with Bakugan strategy to outmaneuver foes. Preferring solitude, he gradually learned to rely on his friends, showing deep loyalty despite his lone-wolf nature. He distrusted reckless tactics like inexperienced use of BakuNano, though he eventually adopted them when necessary. His sharp observational skills allowed him to detect deception, exposing impostors and uncovering lies from Ren Krawler and Jake Vallory. Physically, Shun has pale skin, black eyes, and black hair. During Bakugan Battle Brawlers, it was styled in two layers: one across his forehead and a back layer tied in a ponytail. His attire included a dark sleeveless shirt under a purple jacket with a triangular back and black pants with brown zipper designs. In New Vestroia, he cut his ponytail, wore a black turtleneck, elbow-length gloves, Vestal jeans, and black boots, later adding a knee-length green vest. For Gundalian Invaders, he adopted a green ninja-style shirt with purple and gold trim, black pants, and purple/green boots. In Mechtanium Surge Arc 1, he wore a light green shirt under a white shirt with dark green trim, a dark green choker, tan pants, and light brown boots. In Arc 2, he switched to a green jacket, green shirt, white pants, and black shoes. His primary Guardian Bakugan was Ventus Storm Skyress, a gift from his mother. During New Vestroia, after Skyress was captured, he partnered with Ventus Ingram, who evolved into Master Ingram. Skyress later chose to remain in New Vestroia, passing her role to Ingram. In Gundalian Invaders, he used the synthetic Ventus Hawktor, while Ingram's fate was unconfirmed. For Mechtanium Surge Arc 1, he partnered with Ventus Taylean. In Arc 2, he used Ventus Jaakor and temporarily commanded Darkus Skytruss and Darkus Orbeum, later combining them into Ventus/Darkus Magmafury. He also utilized Battle Gear like Silver Swayther and Battle Suits such as Ventus Fortatron. Key battles marked his development: He defeated Runo and Marucho to avoid joining the Brawlers initially but later allied with them against Masquerade. He deliberately lost a battle to enter the Doom Dimension, confronting an illusion of his mother which triggered Skyress's evolution. He expressed anger upon discovering Alice was Masquerade, temporarily damaging their relationship. In New Vestroia, he infiltrated the Vexos, battled Shadow Prove using Mechanical Darkus Hades, and reconciled with Skyress before she entrusted him to Ingram. During Gundalian Invaders, he collaborated with Fabia against Gundalian forces. In Mechtanium Surge, he temporarily assumed leadership when Dan struggled with Drago's corruption, later mastering dual-attribute battles with Ventus and Darkus Bakugan. Shun evolved from a solitary tactician to a trusted team member, maintaining core traits like analytical thinking and calmness while adapting to new challenges. He led in Dan's absence and mastered advanced brawling techniques. His relationships, particularly his loyalty to Dan and mentorship of Komba O'Charlie, reflected his growth in valuing teamwork without sacrificing his strategic independence.