This one requires lot of experience.
1. Go find and kill Hargvar the Hairy without killing any of his guards.
2. After Hargvar is dead. kill one of his guards and travel to the castle.
3. There will be a man you haven't noticed before in here. Talk to him and say "Who are you?" After that he will tell you he's a worldwide thief and will give you money if you don't report the gaurds. Say "No, I don't think so". He will attack. Run out and find an alpha snarl. You must let the alpha snarl kill the man. If the alpha kills him you get $20,000. Repeat this as many times as you like.
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