Fire Dragon

The Fire Dragon was a creature from Muspelheim that was chained in the domain of Surtur, the ruler of the Realm. After the temporary defeat of Surtur at the hands of the God of Thunder Thor, the Dragon freed itself and tried to kill the Asgardian warrior, only to be beheaded by the Bifrost Bridge.

Battle of Muspelheim
During his confrontation with Surtur, Thor, which managed to release himself from his imprisonment by Surtur, he was freed and had spoken with Surtur about the oncoming Ragnarök prophecy ,which Surtur claims it cannot be stopped and needs to happen, presumably he knew about the threat of Hela.

When Surtur shown his malevolence and taunted Thor about the fact that the latter's father, Odin is no longer on Asgard, the thing led to a lengthy battle on Muspelheim. During the battle, Surtur's creatures stormed on the Asgardian which used the Mjolnir hammer to defeat them all. In the process, when Surtur saw no option to overpower Thor ,he sent the Fire Dragon.

Death
When Thor called for Skurge to open up the portal of the Bifrost Bridge for him in order to allow himself to return to Asgard, the Fire Dragon had succeeded to come to the Bifrost Bridge with Thor himself, which after passing through the portal and returned to Asgard, had killed the monster moments after he arrived on Asgard by slicing the beast's head over the floor and destroyed it, causing the Dragon's yellow blood to be spilled over Skurge and the other Asgardian women which were with him.

Allies

 * Surtur - Master
 * Fire Demons

Enemies

 * Thor
 * Skurge - Accidental Killer

Behind the Scenes

 * The Fire Dragon was featured in the dark ride  at, in the special Halloween themed ride Monsters After Dark.