Italy signed a peace treaty in 1947 that compelled it to return looted items within 18 months.
The museum's current director, Peter Keller, also allegedly knew about the practice and had visited storage lockers where the looted items were kept.
These looted items will be placed into the player's own inventory.
They returned the looted items and apologized in order to stave off retribution.
Today visitors pour into town chiefly to see the cathedral treasures, after the notoriety that accompanied the return of the looted items in September 1993.
Most of the looted items were tiny beads and amulets.
Some 26,000 railroad cars full of art treasures, furniture, and other looted items were sent back to Germany from France alone.
Demonstrators broke into the Egyptian Embassy at one point and carried out looted items.
The British Government occasionally returned some of the looted items.
The hope is that forces now guarding Iraq's borders might be able to intercept at least some of the looted items before they are smuggled out.