Ardent is a dwarf who, during Thud!, works closely with Hamcrusher and his fellow deep-downer Grags, wearing the typical black leather flap robe-and-hood of a Deep-Down Dwarf. His beard is trimmed somewhat neater than other dwarfs. He acts as Chief Liaison to the world above for the group of Grags who are looking very hard for something under Ankh-Morpork.
He discovers to his dismay that Ankh-Morpork Law goes all the way down when applied by Sir Samuel Vimes during the events of Thud!. He is even more dismayed when Bashfull Bashfullsson proves that the hand is faster than the axe. Presumed dead, (like Moriarty at the Reichenbach Falls), he resurfaces (although as a Deep-Downer he would not use the phrase) in Raising Steam as an advisor in the court of Low-King Rhys Rhysson. Here, he is ostensibly putting the case for the old ways. However, he is also deeply involved in more militant ways of restoring the Old Order to the world of Dwarfs, sowing discontent among the Dwarfs, organizing attacks on the 'abominations' of progress like the Clacks Towers and the railway. When he feels secure enough to do so, he usurps the Low Kingship while the king is away at a conference in Quirm and provokes a civil war among the Dwarfs. He is thwarted by the Low King and his allies, Vimes and the Watch, Vetinari, Moist von Lipwig and the Trolls, Goblins and free thinking progressive Dwarfs who return the Low KIng to Schmaltzberger. At the end of Raising Steam he is arrested and held for trial, the Low King/Queen refusing to act in the old Dwarf way as judge, jury and executioner. However, his fate is likely sealed because the Low King/Queen decrees that the jury will be made up of people from the wedding party where the bride was murdered on Ardent's orders and the families of those he terrorized.
Ardent is appropriately named for a fundamentalist Dwarf- "ardent" meaning "passionate, fervid, intense" with an archaic meaning of "inflamed" or "burning"