Black Dranzer is the Dark Phoenix the dark side of Dranzer who is also the companion of Kai Hiwatari. He is the Phoenix of Darkness. and is also regarded as Lucifer's harvester. His first appearance in Beyblade was when Kai sneaks into the abbey to find out their secret, where Boris/Balkov offers the blade to Kai.
Then Kai finally accepted his offer and claimed Black Dranzer's power and used it to capture the bit-beasts of the All-Starz and the White Tigers team.