Ep. 28: The Dark Mist Rises, Part 1

28

Vector, under orders of Don Thousand, forms an alliance with Number 96 in order to obtain one of the Mythyrian Numbers. Vector and Number 96 obtain the "Number" in the ruins first, and are waiting for Yuma and co. with this new power in hand. Upon doing so, they force Astral to a Duel in order to claim the card. (Source: Yu-Gi-Oh! Wiki)