Amulets

Two major factions exist within the Arendellian garrison, each supporting either Elsa or Anna for the throne. These faction members identify themselves as Knights, and wear silver pendants filled with raw, liquid mana. The mana in these necklaces aligns its properties to the allegiance of the wearer, making them interchangeable. When worn by a Knight of Elsa, the amulets glow blue and swirl with images of frost. When worn by Allies of Anna, they glow red and dance with flames.

The one exception to this principle is if an exceptionally powerful magical force approaches the wearer. For example, when Hikari Oni leans over Anna to kiss her forehead, her amulet turns red.

It is discussed, but not yet demonstrated, that shattering an amulet will result in a violent and deadly effect.