Bill the Duck

You will need to have 5 gifts to do this one. In the first village, give 5 gifts to a man called Brody(he should be inside a house). He will say stuff like he doesn't have anything for you but once you give all the gifts he will tell you that the ducks eat anything and they sometimes eat gold. After you done this, go north east to find these ducks and run into all of them. A message will say you got 500 gold coins and the achievement will come up too.