Scepter of Tn'kaneid:

Once per session, you may cast the Clairvoyance spell at no Magic Point cost. Magic Malfunctions cannot occur from the use of this artifact. Twice per age, when casting Clairvoyance through the scepter, you may act as though the roll was a natural 20, for the purposes of level of detail for information. When casting Clairvoyance through the scepter, no magical barrier, spell, or non-Legendary artifact may prevent it from working.