Gamabunta is the head toad that is summoned. He is really big and he is about 100 m. He is mostly summoned out when there is a big and powerful rival. He has 2 children toads which are Gamakichi and Gamatatsu. In demon fox chakra Naruto can summon Gamabunta but with regular chakra he can only summon the Toad King's small children. Gamabunta appeared early in the series Naruto, it starts out when Gamabunta and the 4th Hokage are battling the Nine-Tailed Fox Demon. People knew he could talk when Naruto summoned him while training with Jiraiya. Jiraiya shoved Naruto of a cliff to scare Naruto enough to release his Nine-Tailed chakra, but Jiraiya wasn't counting on him to summon Gamabunta which Naruto did.Gamabunta wasn't happy to be summoned at all and at the bottom of the cliff canyon, then Jiraiya ran away fast.
Mostly Gamabunta is a grumpy and apathetic animal. He doesnt want to take orders from no one, unless its a talented summoner and if he or she earns respect from Gamabunta. Jiraiya, Naruto and Minatao Namikaze are the only ones who can ride on his head. He uses Yakuzua Gangster words in Japanese, but he is still a good fighting force. He is protective, he doesnt like to be underestimated. He shows respect to Naruto as if he was his son even though he can be grumpy sometimes. Jiraiya needs a little more help taking control.
Gamabunta couldn't believe a little kid had summoned him. naruto became very angry for that comment. Naruto said that he summoned him so know he is Gamabunta's master. Gamabunta lost patience and threatened to kill Naruto. Gamabunta gave him a submission move and Naruto apologized and Gamabunta declared him as his subordinate. Naruto passes out from summoning Gamabunta and Gamabunta takes him to the hospital.
When the attack of Konoha took place. Naruto summoned Gamabunta to protect himself by Gaara's Sand Burial Jutsu. When Gaara was n his 100% Shukaku form, he still had the same personality. Gamabunta did not help Naruto until Naruto signs a contract saying they are a team, but Naruto was to young to sign. Naruto accidentally summons Gamakichi and he said that Gaara was bullying him and Naruto came to save him. Gamabunta was impressed so he officially made Naruto his subordinate. Gaara makes him fall asleep making Shukaku escape and have his 100% power. Gamabunta couldn't handle the 100% power of Shukaku. But, Naruto and Gamabunta uses a jutsu combination technique were they can combine Gamabunta's power and the Nine-Tailed Demon Fox's power. Naruto got close enough to give Gaara a brutal punch and wake up Gaara. Gamabunta was once again impressed with Naruto, but now Naruto reached his limit and Gaara reached there full limit and so did Gamabunta so it was a draw.
When Jiraiya and Tsunade were fighting Orochimaru Gamabunta was summoned by Jiraiya, Tsunade summoned Katsuyu and Orochimaru summoned Manda
In the Sea Country, Naruto summoned Gamabunta to battle against Umibozu, the Sea Boss. Gamabunta wasn't happy about being summoned in seawater (toads are freshwater creatures), but fought anyway because he was underestimated by his opponent. He and Naruto defeated the otherwise indestructible water creature by evaporating it. Gamabunta then threw Naruto into the air as punishment for summoning him in seawater. However he noticed that he was still happy that Naruto took so much care of his children.
Gamabunta makes his Shippūden debut along with his son Gamakichi when Naruto is informed of Jiraiya's death.
Invasion of Pain
When Naruto is summoned by one of the smaller frogs he appears atop of Gamakichi's head who stood on Gamabunta's head with Gamaken and the Food Cart Destroyer Toad standing beside Gamabunta. He watches as Gamakichi and Naruto leave, with Fukasaku and Shima in tow, to face off against Pein. Watching the confrontation from afar, he is ready when Naruto blasts Animal Realms summons towards him and his frogs, and after Fukasaku lands and gives them the go-ahead leads them into battle. Gamabunta leaps into the air, impaling Animal Realms dog summons on his sword. On the way down he uses the Rhino's horn to impale it through the mouth, though he also lands on top of it. He then returns to watching Naruto's battle, ready to help again if called.
Gamabunta has displayed only two techniques thus far, one being "Water Bullet" where he spits a highly condensed ball of water at his opponent, and "Toad Oil Fireball" in junction with Jiraiya where Gamabunta spits a stream of oil and Jiraiya ignites it with a fire technique. Combination Transformation Fire Release: Toad Oil Flame Bullet Toad Sword Beheading Water Release: Bullet Technique
Elements: Water(main); Wind (Secondary)
Complete List of Justsu: