Irian

Irian, or the Eternal Dawn, is a plane of positive energy. Positive energy, however, can be and often is put to nefarious uses just as necrotic energy can be put to good.
There are many Manifest Zones to Irian on the island of Aerenal, which most believe is what sustains the Undying Court. The famed City of the Dead, Shae Mordai, is built atop one such manifest zone, as is the small village of Shining Valley in Breland, where the very air glows and grievous wounds knit on their own. Some scholars also speculate that these manifest zones are what make the horses of the Valenar Elves so powerful.
In areas with Irian manifest zones, life blossoms. The sun is brighter, colors are more vibrant, and sensations are more intense. For the short period when Irian is coterminous with the Material Plane (which happens for ten days in the month of Eyre each year), positive energy spells are enhanced, but typically only for the hour in which the sun is at its highest. When Irian is remote, the night seems longer and darker and a kind of numbness hangs in the air. These manifestations occur for ten days during the autumn month of Sypheros.