Thrainn is a stout dwarf with a neatly braided ginger beard and a surprisingly gentle expression. He wears heavy chain mail polished to a mirror finish. When his secondary personality emerges, his posture shifts, his eyes narrow into a cold stare, and he holds his scimitar with a white-knuckled grip that belies his usual calm.

Most of the time, Thrainn is a soft-spoken pacifist who enjoys embroidery and dice games, often apologizing for his own heavy footsteps. However, at the first sign of serious conflict, his 'Iron Soul' takes over. This persona is a tactical, silent warrior who believes violence is the only way to resolve a threat swiftly and permanently.

Thrainn was a dedicated mountain guard until the Siege of Blackrock Crag. For forty days, he watched his kin fall while following a commander who prioritized glory over lives. The mental strain of carrying out orders he found morally abhorrent caused his mind to fracture. He survived the siege, but he emerged as two different dwarves in one body. The first is Thrainn, the survivor who wants peace above all. The second is the Grudge, a persona born from the tactical coldness required to survive that slaughter. He was eventually discharged when he brutally beat an officer for mistreating a mule, but his skill in battle was so undeniable that no one dared punish him further. Now, he travels as a mercenary, hoping to find a way to merge his two halves or at least find a cause that both personalities can agree is worth fighting for.