Brisingamen

The Brisingamen is a consumable item in Trials of Mana HD.

Trials of Mana and Trials of Mana HD
One of four class-change items for Riesz, the Brisingamen is generated by a ??? Seed planted in a Magic Pot, and only if she was promoted to Valkyrie for Class 2. The item must be in the party's possession to activate the Vanadis class selection in Class 3.

Alternatively, casts Strengthen on all allies

Etymology
Brísingamen (or Brísinga men), from Old Norse gleaming torc, is the necklace of the goddess Freyja.