To craft the new 291 runecarving items, you must first reach Honored with the new The Enlightened reputation from Zereth Mortis and finish Chapter 5, which is unlocked on week 3 of the patch(1st week of mythic). You can buy a recipe that will teach you a recipe for a new item: the Vestige of the Eternal. Based on your profession, you will need to farm specific items from the new Zereth Mortis zone as well as a legendary item similar to Korthite Crystals called Progenitor Essentia. After crafting the Vestige, it can be used as an optional reagent when crafting a runecarving item to set the ilvl of the item at 291.
Progenitor Essentia also have an additional use: they are used to craft profession gear at ilvl 262. You can only have one 262 crafted piece equipped. These 262 crafted pieces can also be upgraded with a new minor effect via an optional crafting reagent. These additional effects will not be worth using the item over a higher ilvl piece but can give a small bonus in the first few weeks to an unlucky player who hasn’t upgraded from their 252 mythic items.
