Where to get Hellfire Butterfly in Genshin Impact
Hot and hard to find.
Aidan O'Brien 
The Hellfire Butterfly is an extremely rare ascension material in Genshin Impact. It can only be obtained from one place, the Narukami Island: Tenshukaku domain at level 70+. The resource can drop from the Sijourna fight, and can also be converted from Molten Moment and Ashen Heart using Dream Solvent at the Alchemy Table.
The Narukami Island@ Tenshukaku is the home of Raiden Shogun, and players will only get access to it by playing through the Archon Quests in Genshin Impact. During the Archon Quest Chapter 2, Act III: Omnipresence Over Mortals players will have to fight Signora.
Much like the Childe fight, this will then become a repeatable event that players can farm weekly to try and get Hellfire Butterfly drops. Getting the rewards will cost 30 Original Resin for the first 3 weekly boss fights, then 60 Original Resin for each fight after that.
In-Game Description
A warped shard that houses great might. You obtained this from defeating Signora, who unleashed her original power.
The seal of ice was broken under duress, and as her former will surged forth from its pale white prison and she remembered her old name once more, the undying butterfly danced amidst burning flesh and blood. And she remembered her past, wandering the land, spreading the flame, burning away all evil — and she recalled the face of the person she could never meet again.
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