Ser Ardal is member of the Templar Order and the leader of a group of Templar hard-liners known as The Purifiers. Under Ardal's leadership, the purifiers seek to turn the Chantry onto a harsher path by enacting a more brutal and exacting vision of justice.
Background
Ardal is a man of faith, when it suits him. His distaste for Magic doe snot stem from fear so much as jealousy. Ardal believes that strength should rule over weakness and that those in power should be rewarded for taking on the mantle of leadership. To him, magic is a strength that he cannot possess, and therefore he must destroy ir or at least those who can wield its power, to demonstrate his superiority and his right to lead.
Whenever possible, he casts his actions in a light that compares him to the most faithful followers of the Chantry but there are darker moments when he resorts to the simple philosophy of the ends justifying the means. Such is the case with lyrium. Ardal sees the opportunity to secure a quick road to power and a means to defeat the Elevated Brotherhood; a Mage group which opposes his ,once and for all. He also sees that a group of people addicted to lyrium, with him as their supplier, puts him in an even more powerful position and he will do whatever it takes to realize this vision.
Involvement
Ser Ardal is currently attempting to plant members of the Purifiers into positions of leadership and influence in settlements across northern Orlais to begin building a power base for his grand schemes. He arranges to purchase an ongoing supply of lyrium from Ser Blaen, a former Chevalier who now controls a lucrative lyrium smuggling operation. Ser Ardal goes to meet Blaen at a gala held in Lady Sennova's manor in Val Royeaux, however during the meeting a party of adventurers disrupts the meeting.
Ser Ardal is persuaded that the party can offer him a better deal than the soiled chevalier and agrees to purchase lyrium from them instead. Blaen and his entourage attack and Ser Ardal and his templars join with the party to defeat them. Ser Ardal thanks the party and makes arrangements to begin receiving the lyrium before departing.
Ardal refuses to retreat upon realizing that members of the Elevated Brotherhood, which he suspects includes the party are present and fights to the death. He is eventually slain along with his followers, destroying the leadership of the purifiers.