Baldur's Gate Wiki

INVULNER.ITM is an undroppable item that is equipped on creatures the game does not want to die or even be damaged accidentally, or that until some plot element condition is met (which will remove this item from the creature).

This item can take the place of the MINHP1.ITM in some cases, and it is used more frequently in the Baldur's Gate II: Throne of Bhaal or Watcher's Keep areas of the game.

INVULNER grants the following characteristics:

It remains possible to kill a creature equipped with this item in Baldur's Gate II: Enhanced Edition. However, other items are often provided to the creature, to close off any gaps in protection.