Evokers who have fully embraced their divine powers granted to them by the gods, a Symbol of Divinity not only embraces their divine power, but uses it to its fullest extent.
Divine Specialization
Your Evoker's Blast works as normal as if you had chosen the Holy/Unholy Specialization. You do not gain the benefits of the Holy/Unholy Elemental Specialization and instead gain a Deific Gift and its abilities in place of the powers that'd normally be granted by an Elemental Specialization.
Any instance of "Purge" in the Deific Gifts instead adds a flat bonus equal to the unmodified number of rolled dice for the Evoker's Blast for their level (ex: level 9 is a +3, level 12 is a +4, etc.)
This alters Evoker's Blast and Elemental Specialization.