Who is Kaiser Granvorak in Black Clover?

Kaiser Granvorka is the captain of the Clover Kingdom’s Purple Orca squad of the Magic Knights. Kaiser is a humble, polite, competent, and honorable man. He took on the role of Magic Knight Captain for the sake of his fellow squad members, even though he dislikes standing out. After Gueldre Poizot’s removal from his position, Kaiser takes over as captain of the Purple Orca squad and, at Julius Novachrono’s request, attends the annual Star Awards Festival. Kaiser is not surprised when his squad ranks 8th.
Kaiser as Magic Night Vs Kaiser as Elf
He possesses a three-leaf clover grimoire that contains various vortex-based spells. Kaiser uses this magic attribute to create magical whirlwinds that dissipate others’ magic. Vortex magic which allows him to create whirlwinds and dissipate most magic attacks. His whirlwinds are so strong that he can tear apart the ground. This attribute is what makes him the most defensive captain of all.
When Kaiser was possessed by an elf, Fuegoleon stated that Elf Kaiser could take on spirit level magic, he even acknowledged that his attacks were useless against his vortex magic. He was able to defeat him because he outsmarted him by using Salamander as decoy so he could get through his defense’s and punch him. Fuegoleon received some damage from his fight with Kaiser, Kaiser expanded the whirlwind to wash away Fuegoleon’s magic and penetrate his mana skin in the process in order to harm him. As Fuegoleon said, “Sir Kaiser is more than capable of putting a decent fight”.
The Battle of Magic Nights
During the captains’ battle, Kaiser was able to dissipate Fuegoleon and William’s attacks without any problem. They are two of the strongest captains. Specifically, he stopped Fuegoleon’s magic which can break even the best defenses, and one of the giant roots of William’s World Tree Magic.
Kaiser is definitely the weakest captain in terms of offensive capabilities, but he has the best defense of all. Even the captains have a lot of trouble trying to break his defense, cause If he was able to tank the strength of a mountain-sized demon, then he can surely stop most of his comrades’ attacks.
He doesn’t have the raw power that others have, but his defense is what makes him a dangerous opponent. There is no doubt that he is a strong, competent and experienced knight. He is the oldest captain with 49 years old. For something he was promoted to captain and is considered as the Kingdom’s Ultimate Shield.