Smaug

Smaug is a character in a Tolkien character who appears as the main antagonist in The Hobbit, the 1977 film, and The Desolation of Smaug.

Background
In the year 2770, as a young dragon, Smaug had heard of the hoard holding inside Erebor. He attacked Dale, but then came for a greater treasure Girion, the Lord of the City, tried to fire. Arrow after arrow, Girion kept missing. Smaug continued on to Erebor. He had driven the dwarves into exile all the way to Ered Luin (the Blue Mountains). Among the treasure was the Arkenstone, Thrór's stone and a Mithril shirt that would be give to Bilbo Baggins by Thorin Oakenshield. Thorin would also swear his vengeance on the accursed beast.

The Hobbit film trilogy
One day, a hobbit by the name of Bilbo Baggins interrupted the dragon's sleep and hunted down Bilbo until the Hobbit became visible to him through the One Ring. Smaug interrogated the hobbit of his friends' whereabouts, but Baggins did not divulge any of them, but he thought otherwise. Smaug knew of Thorin Oakenshield's attempt for the Arkenstone, where he started to come at Bilbo before the hobbit disappeared. Smaug searched for the Hobbit, and also tried to destroy Oakenshield's and Baggins' friendship. He also tempted to let Bilbo take the Arkenstone, only to watch Thorin suffer. Bilbo slipped the ring on his finger and disappeared, leaving Smaug enraged and Fire at the Hobbit. The next time he spotted Bilbo was when he was with Thorin and the other dwarves who came in to rescue Bilbo, but they fled. This lead Smaug to hunt them down.

The remaining company thought of a plan to split to distract Smaug. He was next seen by Bilbo and the two dwarves and chased Thorin down a hole until Nori intervened and fell to. Thorin told his fellow companions to hide after he enraged the “witless worm" on the pillars' edge. They outsmarted Smaug. The dragon than came an attack on Bilbo before the hobbit ran to the Gallery of the Fallen Kings. They attempt to burn the dragon’s skin. The plan fails miserably while Smaug runs off to destroy Lake-town.