Olympia: The Age of Gods PBEM (Oct 4 2000)
This artifact reduces the price a noble pays for goods in a city or guild market by the specified percentage, e.g., a +20 bonus Improve Bargaining artifact reduces prices by 20%. This applies only to goods sold by the city or guild (not other players) and the discount is applied only at the end of the sale (i.e., not when the market is determining the highest bidder).