Received from: Bouncer [Hatmandor Sewers] (M21:7)
The man will offer you to participate in his favourite game "Buyout". Accept, leave the sewers and head to the gate leading to verita mines [Hatmandor Region] (M12:23), where you'll meet with Bouncer again. You have to rob three guards standing by the gate before the time runs out - you have 5 minutes. That's more than enough time, but be sure you've got the pickpocket skill developed, otherwise you won't be able to steal from anyone.
You have to reach a treasure, with three snakes moving around it - wait for all of them to line up. Collect three useless items and talk with Bouncer (M12:23) to get the reward for winning in the game.