Carbuncle is a magical creature with healing powers that helps Noctis Lucis Caelum in Final Fantasy XV. It appears as a companion in Platinum Demo – Final Fantasy XV, leading young Noctis through his dreamscape. Upon completion of the demo, the player can name the Carbuncle and it appears in the full game with the name the player gave it.
Carbuncle is based on a recurring summon from the Final Fantasy series. Its incarnation in Final Fantasy XV resembles a fennec fox with its large ears and small snout. It has pale blue fur, brown eyes, and a puffy tail. There's a horn made of ruby on its forehead.
Carbuncle is given to the eight-year-old Noctis as a wooden figurine after he was attacked by an imperial Marilith. Noctis was badly hurt and fell into a coma. While he recuperates his father King Regis places a Carbuncle doll next to the unconscious Noctis. Carbuncle appears to Noctis in a dream world of his making, and communicates with him through a smartphone. Carbuncle explains Noctis is sleeping and being prevented from waking up by a force that wants his demise, but promises to help Noctis find a way out of the dream.
The young Noctis follows Carbuncle through a forest path and a room full of toys and other objects while in a shrunken state. Carbuncle helps Noctis fight the monsters that appear in his dream, and, finding their way to the Citadel, an Iron Giant appears. Noctis transforms into an adult and fights the Iron Giant with his full power while Carbuncle helps him by reviving him if he falls in battle. After the Iron Giant is felled Carbuncle leads Noctis to the Regalia, Regis's car and a place Noctis associates with safety and being with his father. Carbuncle tells Noctis its name and disappears as Noctis awakens, while promising to be with him and help him.
When Noctis awakens his father is by his side and the Carbuncle doll is next to him. Carbuncle appears to some kind of spirit animal to Noctis. It is a magical creature that guides him that others cannot see. In Final Fantasy XV Prologue Parting Ways that depicts the day before Noctis's scheduled departure. Noctis makes sure to take the Carbuncle figurine with him to "keep them safe on the road".
Carbuncle acts as the player's guide. The player must follow it to get to the next area while the various game mechanics are being explained. Carbuncle will revive the player if they fall in battle, so the player can't get Game Over in the demo. Completing the demo lets the player name Carbuncle.
Carbuncle hosts the tutorial the player is advised to take before starting a new game.
In Easy Mode Carbuncle appears when the player enters critical condition to heal Noctis, and can appear in both dungeons and the open world. He can appear once per battle. He can also randomly appear in the background of photos taken by Prompto.
In the free holiday DLC Noctis is visits a carnival in Altissia with Carbuncle, who will follow him through the various attractions. After accumulating enough medals, the player can attend the fireworks show with Carbuncle.
Carbuncle was a mythical creature reportedly sighted in the Americas by Spanish conquistadors. It is described as a small creature, either a bird or a mammal, that has a gem in its forehead crystallized from the brain of a dead dragon. According to myth, it is good luck to catch a carbuncle. A carbuncle is also an archaic name given to any red cabochon cut gemstone. The name applied particularly to red garnet.
- "Carbuncle surprise" was a promotional campaign the player could partake in by pre-ordering the game.