Byonko is a talking frog mamodo originating from the Mamodo world. He tends to get upset easily and is always anxious, especially about making friends. In battle, he often boasts about his skills rather than worrying about the enemy.
At one point, Byonko befriends Zofis and assists him in gathering the Ancient Mamodos that were sealed away in stone tablets. Zofis could revive them as his servants. Believing that he and Zofis were true friends, Byonko, along with Penny, joined Zofis and became his first two assistant pairs for the Ancient Mamodos. They wielded control over these ancient beings, commanding them to attack and destroy Zatch, Kiyo, and their other friends.
Byonko's abilities are primarily slime-based, perfectly matching his frog-like nature. His powers mainly involve stretching his limbs or shooting out slime bubbles. He is also shown to possess immense strength, capable of knocking down Demolt.
Spells:
Gigano Ribbisto: An unknown spell that Byonko attempted to use to save Penny from Zatch's Bao Zakeruga. However, he was unable to cast it since Alvin was not present. (Attack)
Gigaro Nyururuk: Byonko's hands and feet stretch to an incredible size. (Attack)
Raja Nyurusen: Creates numerous slippery, green bubbles that cause enemies to slip and fall, preventing counterattacks. (Immobilization)
Giga Nyushield: A green shield made of slime shaped like a crown. (Defense)
Shin Nyushield: Byonko's strongest spell, mentioned in Zatch's golden spellbook. It forms a slimy membrane around a spell to reinforce its strength. (Assist)
Source: ZatchBell Wiki
