Artifacts are items which a hero may find while out questing. Monsters usually carry them around and some even fall from the sky from time to time.
List of Artifacts
A list of artifacts the hero is currently carrying appears in their inventory. The hero will sell them all for gold when they next visit a town. That is their only use hero knows about on his own.
However, there is a plethora of special artifacts with special abilities. Most are very rare though.
Very rarely, the hero may be able to combine a few artifacts into a rare and expensive bold artifact.