Duras

Duras is a Berserker of the Warrior caste and the first non-player character (NPC) that the player will encounter as he has taken up the duty of recruiting new people to the Berserker faction. He is also available as a companion to the player. Favoring a sword and shield, he can also fight with bow and arrow from range.

Location
In the region of Edan's Berserker city and main base, Goliet, head to the highest point holding the ruins of a hotel. He is next to the concrete stairs leading up to the hotel.

Tooth for a Tooth
Speak to Duras after you have settled in Goliet to initiate this mission, during which you'll help him figure out who killed the warrior Askor.

Question Irdor directly south of Goliet (find him next to the World Heart) to find he's not the killer.

Question Geron a little east of Irdor to learn he prefers bows to swords so he's likely innocent.

Question Barin south of Small Camp to learn he was good friends with Askor and has no motive.

Find Thorgal north of Converter in Edan and tell him he seems undermanned to initiate The Missing Man, which will send you on a mission to find Rock (your final suspect). Ask him about Askor to learn he was too busy protecting a World Heart to murder anyone, and that his ambition to become a Paladin might've been his undoing.

Head north past Thorgal to find Rock (note there are some extremely dangerous mutants and a Stalker here), who it turns out is fed up with the Berserkers and wants to become an Outlaw. Ask him about Askorto learn he has a solid alibi.

Return to Duras with what you've learned and he'll act suspicious then tell you to see what Barin might have hidden in the Valley of the Damned. Ask him to come with you to have him join you as a companion.

Head for the Great Lift and find the Hidden Casket on the cliffside just past the gate. Return to Duras and accuse him of the murder, which he'll confess to, although say it was in self defense.

The Judgment
If you tell Ragnor what Duras said, he'll distrust him for not coming to him with the truth and give you 1,000 shards.

When you go outside, Duras will attack you. Kill him to complete the mission (be careful to avoid citizens getting caught in the crossfire), noting he has both powerful ranged and melee attacks. Tell Ragnor what happened to receive 500 shards.

Alternately, lie to receive 1,000 shards and complete the mission, or frame Barin to receive 1,000 shards and receive a mission to take down Barin. When you approach him, he'll bribe you with 350 shards. If you let him go, you'll receive 200 XP; if you kill him, you'll receive 100 XP and no shards.

Turning Him in Will result in him dieing. Protecting him will result in his recruitment as a companion.