"The frightful king of winter ruled from his crystal splinter, and all around would bow to him alone. If one misspoke a single word, and the mighty dragon overheard, frozen death from him was quickly blown." – written about Tymofarrar's sire
Tymofarrar is a white dragon who rules a tribe of kobolds in the Nether Mountains, the same kobolds who raided Hilltop at the beginning of the Shadows of Undrentide campaign. While still young for a dragon, and not yet at his father's level of power, he can still be a formidable foe. He has also been reported to occasionally enjoy assuming human form so he could walk into Hilltop and eat pie.
As the campaign begins, Tymofarrar was in an agreement with J'Nah to jointly attack Hilltop and retrieve four artifacts held by Drogan Droganson. However, he suspected that he was being tricked into taking the smaller share of the treasure, so he ordered his kobolds to begin their raid early. In this way, he planned to inspect all four artifacts before possibly relinquishing any to J'Nah.
His plot was foiled when J'Nah's gnolls attacked the returning kobolds; only one of the artifacts (the mask) was delivered to the dragon. This show of temerity by J'Nah greatly annoyed Tymofarrar, and he likely would hunt and slay her, but he was wary of her superiors. Instead, he sought to employ the player character to slay the witch for him, with a promise of gold, magic, safety for Hilltop, freedom for Deekin Scalesinger, or the sole artifact Tymofarrar had recovered. He would even provide a flask of powder, designed to play havoc with J'Nah's unique physiology, so that the execution of his revenge might be more swift. (Specifically, the powder interrupts her actions for 4 seconds and deals 20 damage to her.)
Tymofarrar's fate lies in the actions of the player. If his offer is refused, or if the J'Nah is killed without the player obtaining the dragon's oath to seal the deal (he is an evil dragon, not one to be bound by lesser statements), then Tymofarrar attacks and must be killed. As an exception, characters having a level of bard or rogue or having an intelligence or wisdom of at least 15 can talk the dragon into keeping his word without an oath. If Tymofarrar goes through with the reward, the player can still opt to kill him, but letting him live is also an option. (In fact, wise characters, those whose wisdom is at least 14, can convince the dragon to become Hilltop's guardian instead of merely not sending more raiding parties to the village.) If allowed to live after J'Nah is dealt with, Tymofarrar is willing to bargain for the two plot keys he possesses—the mask artifact and Deekin's freedom—if they were not obtained earlier as rewards. (The former is optional, but the latter is required to advance the plot.)