Welcoming at Mafia Land is the 31st episode of the Katekyo Hitman Reborn! anime.
After arriving at Mafia Island, presses rushed to Reborn to give an interview but Reborn says he'll pass. Reborn explained to Tsuna that he's famous at Mafia Land. Before Tsuna and the others can have fun, Reborn states that Tsuna has to go to the reception office. Once there, Tsuna says that he is the representative of the Vongola Family. The receptionist asked if they have any invitation to which Tsuna answered none. The receptionist said that he'll have to pass a Mafia Exam. Tsuna was given 1,000,000 Euros. and his test was to bribe the man (that has ties with the government) properly. But netherless, Tsuna failed.
Tsuna was hurled in a subway. Reborn was also with him and says that their Under Mafia Land. Once the subway stops, Colonnello asks who they are to which Reborn greeted him. Upon seeing Reborn, Colonnello fired his gun at Reborn. Reborn easily dodged and shots back to which hit Colonnello. After firing at each other, Colonnello asks why'd they drop by. Reborn says that Colonnello will train Tsuna. Those who have been founded guilty of unauthorized entry on Mafia Land are given a single chance. Colonnello orders Tsuna to jump at the whirlpool. Tsuna won't listen so Reborn and Colonnello beat him up. After kicking him by both Arcobaleno, Tsuna drowned at the whirlpool stating that he can't swim.
Before Tsuna could rest, Colonnello and Reborn continue to "train" him: falling rocks, hole pits, and beating him up. Soon, Gokudera and Yamamoto arrives through another subway. The reason they came was to fetch Tsuna. Reborn threatens to train the both of them, too. But before they could start, the alarm sounded off stating an enemy attack. Reborn says that it's the Carcassa Famiglia.
Reborn and Colonnello's Pacifier glows, Colonnello says that there is someone they know among the Calcassa. Reborn says that the only one who would attack is Skull. 3 Battle Ships arrives and fires at the island. Colonnello says that he'll let it slip but falls asleep. Reborn adviced them to take the subway before taking a nap. When they have found the exit, they found everyone evacuating at Mafia Castle. Then 3 (hopeless) Family, Difo Famiglia, Beccio Famiglia, and Nuovo Famiglia, argued to who will lead the battle. Gokudera rants that Tsuna is the one who is supposed to lead them all to which Tsuna panics.
Skull's men arrives and started firing while the other Families fought back. Before they could advance, Skull appeared. Gokudera throws his bombs at him which was deflected. Tsuna points something behind Skull. One of the ally Family states that Skull controls an armored octopus. Reborn arrives but was strangled by the octopus. Skull gives another command to the octopus but the octopus was confused. Reborn says that it's because of his left hand. Tsuna recognizes that Reborn used a Fist Bullet at Skull. Colonnello destroyed the Battle Ships and Skull was punished by Reborn.
When Tsuna, Hayato, and Takeshi thought that they can enjoy now, Nana informed them that they are leaving.