Xanxus

How Xanxus joined the Tourney
Xanxus is the current leader of the Varia, Vongola Ninth's adopted son, and was the main antagonist of the Varia Arc. During the Varia Arc, he and Tsuna battled for the Sky Vongola Ring and the position of the 10th Vongola Boss. Later, in the Future Arc, he remains the leader of the Varia and leads a raid against the Millefiore, taking their Headquarters. He battles against Olgert and one of the Fake Funeral Wreaths, Rasiel, as well and easily wins, showing that he has grown much stronger in the future.

After the war in the future, Xanxus trains for the second Tourney and learns that the thought to have been extinct Air Nomads have been resurrected by the long forgotten Dragon King, among them being Gyatso.

How to unlock
For both methods, you must fight Xanxus at Vendicare Prison. Alternatively, you can avoid clashing with him by wishing for him from Black Star Shenron or purchasing him for 700 Smash coins in the Smash Store. After defeating Xanxus, wishing for him from Black Star Shenron, or purchasing him from the Smash Store, the announcer will say "Someone else has joined the Tourney!" after a Smash Ball appears on the lower-right corner of the screen with a message saying "You can now use Varia's leader, Xanxus!" He will be seen left of Kawajiri, right of Fine, above Negasonic Teenage Warhead and below Leoneed.
 * Clear Man the Meat Level 3 with Gokudera.
 * Play 2900 matches

When highlighted
Crosses his X-Guns together.

After the announcer calls his name
Xanxus shoots fire in multiple directions as the camera zooms saying "Some just like the battlefield hot!"

Flame of Wrath (Neutral)
Xanxus shoots a powerful fireball at his opponent.

Bocciolo di Fiamma (Side)
Xanxus uses one gun to fly around the target and the other to shoot his target from different angles to form a flower bud at the target's feet.

Esplosione di Stelle (Up)
Xanxus jumps into the air while upside down shooting fireballs below him.

Scoppio d'Ira (Down)
Xanxus unleashes a barrage of Flame simultaneously that, because of their density and grouping, appear to fuse together into one large super-powerful blast.

Colpo d'Addio (Hyper Smash)
Xanxus charges his guns with his Flame of Wrath and fires two extremely powerful bursts of Flame.

Martello di Fiamma (Final Smash)
Xanxus shoots mutiple Scoppio d'Iras at once.

Victory Animations

 * 1) Xanxus steps forward and forms a ball of energy in his hands saying "I actually enjoyed this combat fest!"
 * 2) Xanxus spins his X-Guns then shoots them saying "Heh, they won't recognize your corpse."
 * 3) Xanxus thrusts his right gun then swings them four times saying "All your efforts do is guarantee third degree burned faces."

On-Screen Appearance
Xanxus jumps to his point and readies his X-Guns saying "You expect to get in my way? It'll only last seconds!"

Trivia

 * Xanxus's rival is Aang's long dead Air Nomad friend, Gyatso.
 * Xanxus shares his English voice actor with Skowl, Sicilian, Gyro Zeppeli and Daryun.
 * Xanxus shares his Japanese voice actor with Makoto Shishio.
 * Xanxus shares his German voice actor with Polymar and Kurow Kirishima.
 * Xanxus shares his Arabic voice actor with Jerid Messa (in all his Mobile Suits), Shaheen, Shew, King Enma, Shocker, Franky, Alex Mason, Zeed, Yamato Kikkawa, Skull Bozu, Rundas, Alex Mason, Jinei Udo, Genji Togashi, Android 15, Grant Danasty, Raditz, Broly, Zato-1, Potemkin, Captain Ginyu and Mercenary Tao.
 * Xanxus shares his Mandarin Chinese voice actor with Ichigo Kurosaki, Rashid, Corrin A, Jotaro Kujo, Yuto Kiba, Dunsparce, Zhu Ran, Isaac Netero and Dino.