Brisingamen is an item in Fire Emblem Heroes . It's an object that allows a person to use the ability and powers of a victim as long as the victim is wearing the necklace. It is used by Freyja to control her twin brother, Freyr, and bend the real world to her will. After Freyr is killed, the item is rendered useless.
In Norse Mythology, Brisingamen was a necklace worn by Freyja created by the dwarves and is never seen without it. The name Brísingamen can be interpreted in two ways. The second part, “amen” means necklace of torc. The first part, “brísingr” could be a poetic term for fire or amber, suggesting that Brísingamen meant necklace gleamed like the sun.