The Lady of Rolika: A Frostmarked Tale - The Frostmarked Chronicles, #3.5

A fallen goddess cursed for eternity. An undying sorceress sworn to slay her. Only one can be The Lady of Rolika. Kostroma once held the earth in her grasp. But that time has long passed. Cursed because of the gods' lies, she's spent lifetimes clawing back her power to punish them for betraying her. Now, she's known only as 'The Lady, ' and Rolika is her city. Then the witch arrived. Bringing promises of destruction at the hand of the goddess of winter and death, Minna has met Death too often to count.
Each time, her goddess has brought her back, and each time, less of her soul survived the return. It doesn't matter. Her goddess demands she kill The Lady and take her place. Minna won't fail. A story of revenge, sinister magic, and hope amid the darkness, enter The Frostmarked Chronicles' world of Slavic mythology with this tale inspired by the legend of Kostroma and Kupalo. Note: This novella is intended to be read after The Daughters of the Earth and contains spoilers for the first three books of The Frostmarked Chronicles.