Random treasure

In addition to fixed items, a great many creatures in game have random treasures in their inventory, those treasures can be stolen, and will drop upon the creatures' death.

The exact item(s) generated depends on which random treasure files the creature holds, each placeholder file will generate one item from their pool (row). RNDMAG01-03 & RNDTRE01-06 files have a bell curve, thus more likely to get items in the middle columns, while the others are supposed to have an equal drop chance for all items in the row. If the “items” listed do not exist in-game, or are undroppable, then if chosen by chance, no items will be generated.

The item is determined when the creature is loaded, so the first time you enter an area. Only creatures that have respawned or are scripted spawns would change when reloading an area.

BG1
With installed

BG2
With installed

BG1EE
With installed

Sources & references

 * Special thanks to kjeron for the explanation on the mechanics behind the scene