|Hair||Light Brown (Normal)|
|B-Daman||WBMA Proto 01 (Normal)|
|Japanese Voice Actor||Yuuko Sanpei|
|English Voice Actor||Melissa Fahn (credited as Johanna Luis)|
Rudy Sumeragi (Japanese: 皇リュウジ (すめらぎ), Sumeragi Ryuji, Ryuji Sumeragi) is a character appearing in anime series, B-Daman Crossfire. His B-Daman is WBMA Proto 01, but he used Smash=Dragold while under the influence of its Golden Dragon B-Animal.
While possessed by Dragold, Rudy was considered the main antagonist of the first season.
Rudy is a short preteen boy often seen with a kind expression on his face. He has a short light brown hair and green eyes. He wears a white jacket with red sleeves and black collar. Underneath, he wears a light blue shirt. He also wears dark blue pants that reach up to his ankles and that which has a yellow handkerchief in its pocket. Lastly, he wears a pair of predominantly yellow sneakers.
While controlled by Smash Dragold, Rudy's light brown hair blazed into spiky blonde and his face is now noticeably over-confident.
In his debut all up to the events leading up to that incident in the North Sumadora Ruins; Rudy is an optimistic boy with great admiration for Riki. Rudy would even go as far as to dare the blizzards of the Northern City just so that he can follow up to Riki. Despite that, Rudy is not a regular fanboy because he, himself, is a highly-skilled player as he had exhibited during the West City Grand Prix and in the Park Exhibition Match against Riki and Simon.
However, deep within Rudy's idolatry for Riki lies intense jealousy over the fact that Riki has a cooler B-Daman, and that Rudy himself had already desired having his own Dragon-Type B-Daman. When Rudy lost his WBMA Proto 01 inside the ruins, he was totally consumed with the feeling of despair. This is when the spirit of Smash Dragold took advantage of him.
Under the influence of the Legendary Golden Dragon; Rudy is easily said, a power-tripper. He had discarded his bonds with Riki and the others while accepting Novu as his henchman. Eventually, Rudy also discards Novu so that the former can take over the WBMA and the world himself. Rudy's power-tripping is partly because of Dragold's influence and his own jealousy towards Riki. When he was freed from Dragold's mind control, he became remorseful about his transgressions, as evidenced when he started crying.
- His family name "Sumeragi" is Japanese for Emperor while his given name "Ryuji" means The Next Dragon. Altogether, Ryuji Sumeragi means The Next Dragon Emperor. This is fitting for his Dragold-possessed persona.
- He is the second dragon-type user that never used a Heavy/Metal Core (the first being Basara, who would eventually use the Heavy Twin Core in the last few episodes of the season).
- He shares his first name with Ryuji Goda from Yakuza game series, which both become last opponent of respective main protagonist (Riki Ryugasaki and Kazuma Kiryu)