Hyetta
Lake-Facing Cliffs (Liurnia)
Frenzied Flame Seal
Lord of Frenzied Flame
Hyetta is a blind maiden seeking guidance and shabriri grapes along Liurnia's roads. Her questline is deeply tied to the Frenzied Flame, the most destructive Outer God in Elden Ring. By following her quest you gain access to the Frenzied Flame Seal and eventually the Lord of Frenzied Flame ending — the ending that burns everything to ash.
Meet Hyetta on the cliffside. Give her a Shabriri Grape (obtained from Irina's quest in Weeping Peninsula).
Second encounter. Give her another Shabriri Grape found in the ruins.
Third encounter near the dead maiden. Vyke invades you here. Defeat him for the Fingerprint Grape.
Give Hyetta the Fingerprint Grape. She asks to become your Finger Maiden.
Hyetta sits at the door of the Frenzied Flame. Talk to her, then strip naked and open the door to inherit the Frenzied Flame. Hyetta disappears afterward.
If you inherit the Frenzied Flame before completing all grape steps, Hyetta disappears permanently. Shabriri Grapes are from specific fixed locations — you can miss them if you skip Liurnia exploration. Inheriting the Frenzied Flame locks you out of all other endings unless you use Miquella's Needle.
Pro Tip
Do not open the Frenzied Flame door unless you want that ending. It locks you out of all other endings permanently unless you reverse it using Miquella's Needle (obtained from completing Millicent's quest and used in the Dragonlord Placidusax arena). If you want a different ending, complete Hyetta's quest for lore but do not strip before the door.
The Shabriri Grapes Hyetta requests are dropped by Frenzied Flame NPC invaders across Liurnia. The first grape is from an invader near the Purified Ruins (eastern Liurnia), the second from the Revenger's Shack (southwest Liurnia), the third from Festering Fingerprint Vyke's invasion at the Church of Inhibition, and the fourth can be farmed from the nomadic merchant in Weeping Peninsula or found through alternate sources. If you miss a grape in a location Hyetta has already left, the quest can still continue if you catch her at her next location. Fextralife's Hyetta page has exact coordinates for every grape location.
Hyetta's quest is the prerequisite for accessing the Lord of Frenzied Flame ending. After giving her all four grapes, she reveals that the Three Fingers await beneath Leyndell. At the Cathedral of the Forsaken (Subterranean Shunning-Grounds), remove all armor and let the Three Fingers embrace you. This action triggers Hyetta to appear as your maiden. Unlike other endings, the Frenzied Flame ending cannot be undone without completing Millicent's quest in an extremely specific sequence involving Miquella's Needle. Wikipedia's Elden Ring lore section explains the Frenzied Flame's role as an outer god and the cosmic implications of this ending.