Hydros, also known as Hydorous, is a lion-like Bakugan from the aquatic Aquos faction. He serves as Shun Kazami’s primary Guardian Bakugan in the reboot continuity starting with *Bakugan: Battle Planet*. His history before partnering with Shun remains unspecified, though their bond predates Shun joining the Awesome Ones team. Hydros fights with an aggressive, fast, and ruthless style that contrasts Shun’s thoughtful tactics, yet their partnership complements both battle dynamics and personal rapport. A Darkus variant of Hydros appears under Shun’s doppelgänger’s control in the "Outer Demons" narrative, acting as an antagonistic counterpart. This variant shares Hydros’ core physical traits but aligns with a different faction and master. Throughout *Battle Planet*, Hydros participates in pivotal events: battling Magnus’s Webam and Fangzor during a mountain race for Awesome Ones membership—though defeated, his bond with Shun secured their team position—and aiding a mission to rescue Bear from hunter Strata. Hydros undergoes key evolutions, achieving "Hyper Hydorous" during a partnership-focused episode and manifesting a Diamond Hydorous variant in *Armored Alliance* as a powerful evolution. Sharktar temporarily replaces him as Shun’s primary partner in *Geogan Rising*. His aquatic-based attacks include Aquos Hurricane (spinning water tornado), Claw Cutter (claw slashes), Mysterious Mist (obscuring mist), Hydro Barrage, Hydro Blast, Aquos Blast, Brain Geyser, Aquos Smash, Hydro Burst, Wings of Aquos, Tidal Surge, Lumo Blast, Splatter Attack (Strength Mode), and Rapid Tide (Speed Mode). He utilizes Baku-Gear like "Blutt Storm" and partners with Nanogan such as "Riptide". In the physical game, Hydros appears in Core and Ultra forms across *Battle Planet*, *Armored Alliance*, and *Evolutions* with variable B-Power; Diamond variants show exceptionally high B-Power. He is absent from *Geogan Rising* releases. Epic Character Cards and evolution cards like "Aquos Hyper Hydorous," "Diamond Hydorous," "Darkus Hyper Hydorous," and "Aurelus Maximus Hydorous" expand his gameplay. A non-canon portrayal in "Small Brawl Stories" depicts Hydros clashing with Drago over a game controller, destroying it before reconciling. Hydros’ role in *Bakugan: Legends* is undocumented.