Golden Poo Snake
What you need: Need to be on disc 3, have a mechat, Shoes of Hermes (black device needed for barrier in Ancient Factory (ground floor), Poo Bracelet (blue barrier chest in Jibral castle, gate) and the Crown of the King's Ghost (use the transformation box in the Forest of the Dead).
Location: "Southern Deserted Island". Need a Mechat. Far south of the map.
Stink everyone up (use either fresh garlic, stout garlic, dog collar) - brings them to you.
Equip the main person with Shoes of Hermes and Poo Bracelet. Gives you first hit and easy kill.
Assassin Level 23 - Loot & Assassin Level 32 - Treasure Hunt on Hermes equipped character - Gets you lots of gold, guardian hearts and ancient feathers while you attack the Golden Poos.
Should get between 0 and 40,000 gold every time, this amount is doubled when you have someone with the Crown equipped. On average circa 8,000. Try back attacking. It appeared I got more then. Should take about 3 hours or so but you are leveling at the same time.