Cambio Forma is an ability exclusive to the Animal-type Box Weapons of the Vongola Famiglia. Upon shouting "Cambio Forma", the Box Weapon either merges with the user's equipment or becomes a new set of equipment entirely, greatly increasing their power.
- Leone di Cieli Ver. Vongola is the Sky-attribute Vongola Box Animal. Nicknamed Nuts, it is the only one that has two Formas.
- Mantello di Vongola Primo: Nuts changes into a long, black Cloak. The Cloak is attached to a metal plate on the X-Gloves. The Cloak's ability is to nullify attacks using the Sky's Harmony Attribute.
- Mitena di Vongola Primo: Nuts combines with the X-Gloves and turns into a Gauntlet. While using this, he can concentrate all his Flames into a single attack without charging.
- G's Archery is an ability from the Storm-attribute Box Animal, Gatto Tempesta Ver. Vongola, nicknamed Uri. It combines with the Flame Arrow, creating a longbow made of bones. This Weapon can fire bursts of Storm Flames as well as several Storm Arrows at once. The first Vongola Storm Guardian was given a similar weapon from his childhood friend, Vongola Primo.
- Ugetsu Asari's Four Irregular Swords is an ability from the Rain-attribute Vongola Box Weapon. This Vongola Box is unusual in that it has two Box Animals, Rondine di Pioggia Ver. Vongola and Cane di Pioggia Ver. Vongola, nicknamed Koziro and Ziro respectively. Koziro fuses with the Shigure Kintoki to create a long Sword as Ziro provides three short Swords. It was said that the first Vongola Rain Guardian replaced his musical instruments with similar weapons in order to help Vongola Primo in a time of crisis.
- Knuckle's Maximum Break is an ability from the Sun-attribute Box Animal, Canguro del Sereno Ver. Vongola, nicknamed Garyu. Garyu transforms into a pair of Boxing Gloves and headgear with the Sun emblem in the middle. It improves the speed and power of a punch. The first Vongola Sun Guardian turned to religion after accidentally killing a man, but allowed himself three minutes in a boxing ring in order to save his fellow Guardians.
- Lampow's Shield: is an ability by the Lightning-attribute Box Animal, Bufalo Fulmine ver. Vongola, nicknamed Gyudon. It takes the form of a shield and helmet with the Lightning Crest. As well as being defensive, this form can also fire out a Lightning explosion. The first Vongola Lightning Guardian was said to be a coward and a son of a rich man from another Famiglia who had to be forced into battle.
- Demon Spade's Devil Lens is an ability from the Mist-attribute Box Animal, Gufo di Nebbia Ver. Vongola, nicknamed Mukurou. Mukurou transforms into a set of three lenses. These lenses enable Chrome to see through Illusions and reveal the nature of attacks. The first Vongola Mist Guardian was said to be a man who was said to curse those he glared at through his monocle. When used by Mukuro, it allows him to view the weaknesses and statistics of the enemy.
- Alaudi's Handcuffs is an ability from the Cloud-attribute Box Animal, Porcospino Nuvola ver. Vongola, nicknamed Roll. It takes the form of spiked handcuffs. It can multiply using the Cloud's Propagation ability and contain opponents. Its Propagation speed is even faster than Deisy's Sun Activation ability. The first Vongola Cloud Guardian was said to stand apart from the Vongola Famiglia but was most benevolent towards comrades in times of need.
The Varia, or at least Xanxus' Box Animal from 10-years-later was recreated in the present as Armatura di Platino Ligre Tempesta di Cieli, nicknamed Bester. It resides in Xanxus' newly improved Varia Ring and has the same ability to Cambio Forma. Bester manifests and merges with Xanxus' pair of Dying Will Guns and gains the ability to shoot bullets in the shape of a liger.
- Tsunayoshi Sawada's Cambio Forma is an ability Tsuna gains through his Ring of the Sky Version X. Nuts Version X merges with Tsuna and his Vongola Gear X-Gloves and turns into flame-patterned arm thrusters. These thrusters can be used to support the XX-Burner or emit Flames powerful enough to escape the gravity of a black hole.
- Hayato Gokudera's Cambio Forma is an ability Gokudera gains through his Buckle of the Storm Version X. Rather than a bow, when Uri Version X merges with Gokudera, he becomes covered with many straps of dynamite while forming armor on his legs and one arm, and sunglasses which replace his contacts. Gokudera also gains a Pipe-Shaped Igniter which allows him to ignite his Dynamite with Storm Flames, increasing their power and speed.
- Takeshi Yamamoto's Cambio Forma is an ability Yamamoto gains through his Necklace of the Rain Version X. Koziro Version X & Ziro Version X merges with Yamamoto and Shigeru Kintoki gains two katana swords, bracers on both of his arms and metal armored sandals. Yamamoto's clothing also changes to a more traditional Samurai garb outfit consisting of a Kamishimo and a Hakama. On both of his hips rest sheaths, presumably for his two swords.
- Ryohei Sasagawa's Cambio Forma is an ability Ryohei gains through his Bangle of the Sun Version X. After being upgraded with the Vongola Gear, Knuckle's Maximum Break had also transformed, this time to suit Ryohei's needs. Garyu Version X merges directly with Ryohei, without the need for the Sun Enhancement Shot. The three-minute limiter previously placed on this weapon has also been removed. This version now has a Tenth Generation Vongola styled headband, gloves, boots, and armor on the right shoulder. The Bangle also changes in this form, becoming a circular shaped plate with 10 pieces of metal jutting out.
- Lambo's Cambio Forma is an ability Lambo gains through his Thunder Helm Version X. Rather than a shield, when Gyudon Version X merges with Lambo, the Cambio Forma becomes a large pair of horns connected to some armor on the upper body, possessing four switches that change the shape of the horns depending on which switches are pushed. It also has a pair of boots.
- Mukuro Rokudo's Cambio Forma is an ability Mukuro gains through his Earring of the Mist Version X. Mukurou Version X manifests and merges with Mukuro and his trident and turns it into a khakkhara surrounded by rings of text. He also gains a coat that is similar to Demon Spade's, he is able to use all 6 of his paths, and create illusions that can fool master Illusionists.
- Kyoya Hibari's Cambio Forma is an ability Hibari gains through his Bracelet of the Cloud Version X. Roll Version X merges with Hibari. It transforms Hibari's uniform and it acts as a defensive barrier against damage. The chains in Hibari's Tonfas are now able to extend due to cloud flames and can also release spikes, there is now also a blade that can extend from the bottom of his shoes, He can also release miniature handcuffs which can attach to his targets.
- Version Vongola
- Version Varia
- Version X