We are introduced to the B-DaMage, the guide to the B-DaWorld, and her Meowmigos, the three little cats that join her. Down in the B-DaWorld, Armada is the greatest inventor there. He has created the Zero-System B-Daman, Cobalt Blade. But in a flashback, Armada's plans/designs for it were stolen, so he made Cobalt Blade, and has been sent to it's rightful owner. Meanwhile, six years later, we're introduced to an eager 11 year old kid named Yamato Delgado, who was raised by wild cats until he was five, and his pet cat, Tommi. Unknown to him, Wen, Li, and Enjyu have been keeping an eye on him.
We're also introduced to Yamato's second mother, Mie, who owns a cafe in their hometown of Cowtoon. Cobalt Blade keeps trying to reach him by appearing in a wall at his house, but he doesn't seem to know what it is. We learn the sport of B-Daman, in which Yamato sees his first B-DaBattle in town, which is a direct hit battle. He confronts two guys who want to boss around a couple other B-DaPlayers, but he has no B-Daman to fight with. So a mysterious kid named Terry briefly appears to chase them away. Shortly after he meets another kid named Bull.
He admits to Bull that he's never been in a B-DaBattle before, and has never owned a B-Daman. Later that night, Mie celebrate's Yamato's birthday by baking him a cake, and says this is the first birthday he's ever celebrated. As he's about to blow out the candles, a mysterious person arrives claiming to take Cobalt Blade. But Yamato says he doesn't even know what that is, but Gray doesn't believe him. Gray makes fun of Yamato for not having a B-Daman. Just then, the wall starts glowing and Cobalt Blade bursts through and goes towards Yamato's hands. And Gray says that the B-Daman he's now holding is called Cobalt Blade. Gray then challenges Yamato to a Direct Hit Battle.
Mie and Tommi watch on as the match starts. Yamato keeps missing, but Gray's Power Blasts smashes Yamato's shield. He intends to finish the match quickly, and steal Cobalt Blade. After some advice from Mie, Yamato begins to feel the B-DaPower. With his last B-DaBall, he locks onto Gray's Chrome Zephyr as Gray shoots back. But in a test of power, Yamato defeats Gray by scoring a direct hit. Meanwhile, Ababa, Wen, and Li watched the whole thing. But unknown to them, Bull's alter-ego was watching from above and challenges Yamato to a match...