Arcobaleno Trials Arc
13 listed episodes · First aired July 18, 2009

Season overview
The Arcobaleno Trials Arc is an anime-exclusive arc that occurs when Tsuna and his Family traveled back to the past to obtain the Arcobaleno Seals and unlock the true power of the Vongola Rings. The story was supervised by Akira Amano.
Episodes
Back in the past, the 7 Arcobaleno are heading to Namimori to present Tsuna with their trials. Meanwhile, in the future, Irie is telling Tsuna and his friends the details before sending them to the past. He reveals that…
E143Trial #1The next day, Tsuna's class receives two transfer students, Monta Hariyama and Himeko Hariyama. During the break, Tsuna is attacked by Lal Mirch of their time period who reveals she will be the observer of the Arcobalen…
E144The Arcobaleno SealsColonnello continues to overwhelm the two. He is defeated when Gokudera distracts Colonnello for Tsuna to use X-burner on him. Colonnello gives Tsuna the Arcobaleno Seal, which causes all the Vongola rings to glow simul…
E145Guardian Showdown! Cloud and MistMukuro and Hibari continue their battle and Lal appears announcing this is the second trial. Skull calls his pet octopus to combat but Tsuna easily defeats it. Afterwards, he stops Hibari and Mukuro from battling each o…
E146Box Weapon PrototypeTsuna, Yamamoto and Ryohei are called out to Namimori Middle School where they encounter Mammon, who reveals he has Kyoko hostage. Mammon begins Tsuna's trial with a set of riddles which leads them to various locations.…
E147Catch the WindTsuna returns home after completing the trial. The next day, Tsuna receives a letter from the Arcobaleno, Fong, who is also revealed to be I-pin's Martial Arts sensei. The letter tells Tsuna and his guardians to search …
E148Two Successors of the SkyTsuna and his friends discuss who the remaining Arcobaleno are. At that moment, a woman wielding an orange pacifier, named Aria, arrives with Haru and Kyoko and reveals that she will give Tsuna his next trial. Afterward…
E149Reborn's TrialReborn tells Tsuna and his guardians to assemble at Namimori Island for the next trial. When everyone reaches Namimori Island, the trial is revealed to be a battle of Tsuna's family against Reborn. Reborn knocks Tsuna u…
E150A Path Is Closed OffWhile Tsuna's family is recuperating, Verde completes the first stage for his box weapons and decides to seek out the Vongola Rings to help him complete the second stage. All of the Arcobaleno, except Verde, gather at N…
E151Once the Rainbow Is CompleteVerde sends out robots to seek the Tsuna's missing two guardians, Lambo and Hibari. Hibari defeats his robot and Fong defeats the robot pursuing Lambo. Soon after, the other Arcobaleno's arrive to investigate the distur…
E152A Boss' ResolveVerde demands Tsuna and his guardians to surrender the Vongola Ring in return for the Arcobaleno's lives. Tsuna refuses to compiles as the rings will be needed for the future battles and declares they shall defeat Verde…
E153The Final SealTsuna, with his Hyper Intuition, feels that Verde is nearby and finds Verde hiding in a nearby island. Verde declares his research is complete after gathering data on the Vongola Rings' Flames and states he will not nee…
E154To the Next BattleReborn recaps the events occurring between of the Vongola's invasion of the Millefiore base to Tsuna's battle against Genkishi and the revelation of Shoichi Irie.