Source: Tal'Dorei Campaign Setting Reborn

Wondrous item, uncommon

This humble steel rod is engraved with tiny symbols representing different weapons, as well as the monogram “T.D.” A creature holding this rod can speak the name of any simple or martial weapon aloud as a bonus action, causing the rod to transform into an ordinary weapon of that type. When in the form of a ranged weapon, this rod magically creates its own ammunition, which disappears after a ranged attack hits or misses.