The Twin Crowns of Myrmoran were a pair of magical crowns that allowed an empathic link between their wearers. Individually they were known as the Twinned Crown of Yarlith and the Twinned Crown of Uthtower.
After the two kingdoms fell into ruin, both crowns were lost to antiquity for a time. Eventually, the Twinned Crown of Yarlith was recovered by the Cult of the Dragon. It was given to a dragon, Voaraghamanthar, in exchange for his assistance in finding the lost Uthtower and the temple therein that was rumored to contain the remains of the dracolich Chardansearavitriol.
When the crowns were worn by identical twins, as in the case of its original bearers, the wearers formed an even stronger bond. Each wearer could reach into the mind of the other and cast spells the other had memorized or have spells that they cast upon themselves affect their twin instead. It even allowed one to activate magical items held by the other at any distance.
Eventually, the bond between identical twins would become so strong that it would become nearly impossible for either to remove their crown. Over time, neither bearer would be able to live for long without the empathic bond the crowns created.
The most devious hidden power of the crowns was with Iniarv himself. He was able to magically dominate both wearers with his own will. It is not known if or how this power could be exercised by others.