Dain was raised in an orphanage in the city of Thunderstrike, which is in the Principality of Ulek. Dain was always very
big for his age, and his size made it difficult to make friends with others early on. In fact, he was frequently bullied for it. When he became to old to continue his stay with the orphanage, he wandered the streets and made his living by stealing food from vendors and living in storage sheds.
Eventually, he was caught when he broke into Arnold the Carpenter's house in order to swipe a particularly tasty cherry pie he smelled. Arnold, a large old man with a powerful frame, easily subdued Dain. Instead of turning him in to the authorities, however, Arnold decided to take him under his wing. For the next few years, Arnold taught Dain carpentry along with life skills and a strong sense of virtue. Arnold and Dain became an inseparable pair. Eventually, though, a wealthy merchant in Thunderstrike began to start taking over local businesses. As a result, many business owners went bankrupt and were forced out onto the streets.
When Dain and Arnold heard about the chaos this was causing, they were furious. Without hesitation, Dain marched straight to the merchant's residence, followed by a growing crowd of curious townsfolk. When the merchant refused to open his door for him, Dain ripped the door off its hinges, strode inside, made the merchant have a seat, and lectured him on morality and righteousness. He did not leave until the merchant agreed to hand back the businesses he acquired through force, and to make charitable contributions to the poor on a regular basis. Dain kept the door and worked with Arnold to have it modified into a shield.
He became known throughout Thunderstrike as a hero and a defender of the poor, and people began to refer to him as "Thunderfist." One day, Dain decided that he should spread out and do some good somewhere else. When he heard that there was a struggling colony in the Pomarj, he signed himself up has a colonist immediately.
After a few months of frontier life, Dain befriended many colonists and was a reliable worker. He personally helped with construction efforts on the initial wave of colonist housing, and was the go-to man for advice or assistance. When three key members of the colony government were reported as dead, Dain was devastated. The councilor, Quarion, had been very kind to him and the other colonists since their arrival, and Dain looked up to him as a role model. Due to his reputation, Dain was nominated to be the new councilor. Seeing his opportunity to help his fellow colonists express their opinions to the Council, he eagerly accepted the position when it was offered to him by Baron Tyal.
In politics, Dain believed that everyone has different talents and that true fulfillment could only be found when people were able to find their calling, and that everyone was a friend until proven otherwise. Because of this philosophy, Dain made himself a strong advocate for job variation and anti-discrimination so that colonists could be happier and more productive. Unfortunately, he would not live to see a structured plan to embody these ideals come to fruition.
Dain Thunderfist was killed in a particularly brutal fight against a gnoll raiding party. Locked tightly together with his friends on the Council, Dain did his best to deflect incoming attacks and hamper the movement of the enemy. In the tail end of the skirmish, Dain was struck a savage blow in a last-ditch effort to defend a wounded Blake Surtova, the new Baron, from a group of gnoll archers. Already bloody and beaten himself, he was ultimately unable to recover from the wounds he sustained as a result.