Bucking Bronco Arrives! is the fourth volume of the Katekyo Hitman Reborn! series.
Dino, the current boss of the Cavallone Famiglia, arrives in Japan to meet Tsunayoshi Sawada and to reunite with his former tutor, Reborn. During his stay, his pet turtle, Enzio, incidentally turns into a giant several times, but since he loses his physical abilities when his subordinates are not present, he is always unable to help, though Reborn shoots Tsuna with the Dying Will Bullet to stop it each time. However, Tsuna is injured in the process and is checked into a hospital, where each of his friends cause a ruckus when they visit, annoying both the nurse and Kyoya Hibari, who punished Tsuna for their actions. When Reborn later takes control of a class at Namimori, he ends up attacking the students who answer wrong.
- Chapter 026: Three Criminal Brothers (犯罪の３兄弟, Hanzai no San Kyōdai?)
- Chapter 027: Bucking Horse Dino (跳ね馬ディーノ, Haneuma Dīno?)
- Chapter 028: Dino Again (ディーノ再び, Dīno futatabi?)
- Chapter 029: Hospitalization (入院, Nyūin?)
- Chapter 030: Getting Lost (遭難, Sōnan?)
- Chapter 031: New Year's (お正月, Oshōgatsu?)
- Chapter 032: Gokudera's Strengthening Program (獄寺強化プログラム, Gokudera Kyōka Puroguramu?)
- Chapter 033: Parent Participation Day (授業参観, Jugyō Sankan?)