Julio is a Haos battler and his Guardian Bakugan is Haos Tentaclear. Julio was the fourth ranked Bakugan player until Masquerade defeated him. He is presumed to live somewhere in Europe. He is also shown to have a strong rivalry with Runo for being the best Haos brawler. He also sometimes gets called "Q-Ball" by Runo.
Julio, along with other Top Brawlers in the world comes to a "party" created by Masquerade, it is there where he is sent to the Silent Core and put under the control of Naga. When Julio is under the control of Naga, he fights against Runo and Dan, and ends up losing although he sends four of their Bakugan to the Doom Dimension. After that defeat, he fights Dan, Runo and Marucho in one final battle alongside Chan Lee and Klaus von Hertzon, but loses again and is freed from Naga's control. Julio is next seen when Masquerade defeats him and sends Tentaclear to the Doom Dimension.
Julio is currently ranked 9th.
Bakugan Battle Brawlers
- His appearance is somewhat similar to Sid Arkale from Gundalian Invaders and Ben from Mechtanium Surge. Even their Japanese voice actors are the same.
- Of all the five top ranking brawlers controlled by Masquerade, he is the only one who is seen setting his Doom Card upon his first battle against the Brawlers. Billy and Komba set it off-screen, while Chan and Klaus never actually set it in their first battles, which is an error.
Bakugan Battle Bralwers
|Bakugan Battle Brawlers|
|Klaus von Hertzon, Chan Lee, Komba O'Charlie, Billy Gilbert||No Outcome|
|Dan Kuso and Runo Misaki||Lose|
|Dan Kuso, Runo Misaki, and Marucho Marukura (tag with Klaus von Hertzon and Chan Lee)||Lose|
|Hairadee (tag with Komba O'Charlie and Shun Kazami)||Win|
|Centorrior and Druman (tag with Dan Kuso, Marucho Marukura, Runo Misaki, Julie Makimoto, Klaus von Hertzon, Billy Gilbert, and Komba O'Charlie)||Win|