Si Xing Long or Nuova Shenron (Funimation) is one of Shadow Dragons in Dragon Ball GT and the dragon of Four-Star Ball.
Nuova Shenron, like all the other Shadow Dragons, was born from the negative energy of one of the wishes made on the Dragon Balls, in his case, the wish that restored King Piccolo's youth.
Nuova first encountered Goku and Pan when they entered his domain, a city that he had reduced to a waste land. He first attempted to attack them from with a large flame orb and finally introduced himself as the "invincible four star dragon". After hearing about the demise of Haze, Rage, Oceanus, and Naturon which seemed to surprise him, Nuova fought Pan and easily avoided her attack, before he defeated her with a blow to the head. After Goku demanded that the dragon let her go, he did just that and put her out of harm's way. The pair then faced off and Nuova managed to dominate the battle, using his speed and ability to increase his body temperature. Goku found himself being chased by Nuova all over the city and finally transformed into Super Saiyan 4, after almost being destroyed by Nuova's Nova Death Ray attack. The Shadow Dragon responded by shedding his outer shell and increasing his speed even more. Though this evened things out, Nuova's speed still gave him the advantage. Goku drew the Evil Dragon into a series of pipes below the city and managed to catch him off guard. However, he did not finish Nuova and stated that this was his way of thanking the dragon for not destroying Pan when he had the chance. Nuova said that he only wanted a fair fight and the two headed to the surface to finish their battle.
However Nouva's brother, Eis Shenron, appeared and ridiculed and assaulted him for being weak, though Nuova did not retaliate because they were brothers. Eis then fought against Goku himself, while Nuova watched from the sidelines. Goku however managed to easily fight Eis, who was forced to resort to freezing him solid. He ordered Nuova to incinerate him, but the fire dragon instead turned on his brother and used the heat of his attack to free Goku. Eis later used Nuova as a shield when Goku attempted to destroy him with a Kamehameha wave. When the Saiyan finally had the ice dragon at point blank range, Eis asked Goku to spare him if he gave the Saiyan his Dragon Ball (despite believing Eis had brought this on himself). After Goku murders Eis Shenron, Nuova Shenron then gave Goku a medicine that would cure the blindness brought on by Eis's ice claw attack. However, Syn Shenron killed him immediately for his show of mercy. With his dying breath, Nuova said that he was sorry and only wanted a fair fight.
The fight against Omega Shenron
Nuova Shenron made a return during Goku and Vegeta's fight against Syn Shenron (who earlier swallowed the other six Dragon Balls to increase his power 10x what it originally was). After Goku swallowed the Four-Star Dragon Ball in order to stop Omega from reaching his full power again, the positive energy in the Saiyan's body recreated Nuova and he emerged, though apparently loyal to Omega Shenron. He asked to fight the pair alone, which Omega agreed to and the fire dragon managed to outmatch Vegeta. Nuova then fought against Goku, but the two quickly struck Omega Shenron, and Nuova Shenron would prepare to destroy Omega Shenron: The Nova Sphere. As Omega was trapped in the ball, he was able to posses Nuova's body and escape the Fire Cage (due to Nuova's Dragon Ball having been inside of Omega, and therefore still filed with his evil). When this happened, Nuova sorrowfully apologizes to Goku and Vegeta that he had let them down. When Omega possessed Nuova, he quite literally entered his body, and destroys Nuova from the inside. This also allowed Omega Shenron to regain his full power and the Four-Star Dragon Ball.
Like most characters, Nuova Shenron has superhuman attributes and can manipulate Ki in the form of Energy Attacks. He can fly at extremely fast with his wings. He can create a mirror-like lens to use for his Nuova Death Ray technique. Like his brothers (with Syn Shenron being the only exception), Nuova controls a certain element: Fire. He can manipulate Fiery Ki, he can hide inside it, and can control his own body temperature; making it as hot as the sun's surface at 6,000 Degrees Fahrenheit and even higher than that. In Victory Mission, he can posses people like most of his brothers. He is able to use the Instant Transmission technique in Budokai Tenkaichi 3. Like his brother, he can suppress his power level in a shell form. And in Dragon Ball Heroes, he and Eis can change into a Super From.
A very strong punch.
Nova Death Ray
Nuova Shenron uses his Magical Materialization powers to create a large lens. The lens is capable of absorbing Solar Energy from stars. He then fires a huge fiery Ki Wave at the lens, which in turn creates a very dangerous and highly lethal ray. The attack is powered by a star; the attack will not run out and Nuova will not tire out from using it as long as the star remains. He can also just throw the lens itself at the target.
Nuova Shenron charges a spiraling, fiery energy sphere in his mouth. Then, he grabs the energy sphere and charges it in a fashion similar to the Kamehameha. Finally, Nuova Shenron raises his hands and shouts "Nova Star!" as he fires the energy sphere at the opponent, inflicting high damage through a fiery explosion. Nuova's Super Form can use a much stronger version called Inferno Attack.
A move that is heavily mirrored by Pikkon's Hyper Tornado. It is seemingly exactly the same, but with fire instead of channeled air currents.
Sun Gun Attack
Nuova conceals himself within a fiery Ki Ball and launches many Ki Blasts down at the target and the surrounding area. It is very similar to Broly's Burst Eraser attack. As a matter of fact, Nuova himself can also use that attack as well.
Nuova surrounds himself in heat that can absorb heat from Ki Attacks to render them harmless. It also burns anyone who touches him.
Flaming Cage of Agony
Known to most as the Nuova Sphere and as Nuova Shenron's ultimate attack. It consists of Nuova encasing himself and his opponent inside a fiery Ki Cage with Fire Chains that bind them in place. He then detonates the sphere with extremely strong, destructive, and extremely agonizing results. Nuova serves as the nucleus and is not harmed. If any attacks are made against the cage it will detonate automatically. It has been hinted that the explosion could have killed even the likes of Omega Shenron (or at least in his weakened state).
- There are a number of theories behind what made Si Xing Long have honor and morals, something that is unique amongst the Shadow Dragons. One idea is the wish that created him. Since it was a selfish wish, it would have produced very little negative energy, unlike the other wishes, which had good intentions and resulted in more. Another reason may be the Dragon Ball that he possesses. The Four-Star Dragon Ball is most commonly known to belong to Goku and his adoptive guardian Son Gohan. Another theory is it is because of the fire element Si represents, which is sometimes seen a symbol of nobility and a number of protagonists use it in other media.
- His Funimation dub name is a play on the word "nova".