Skill Up & Ascension MaterialOminous bones wielding curses.
Fuyuki: Unknown Coordinate X-C is the best AP-saving location to farm Evil Bone. You'll get around 2x Evil Bone by spending 40 AP.
Fuyuki: Unknown Coordinate X-C is the best time-saving location to farm Evil Bone. You'll get around 6x Evil Bone by spending 150 AP.
Here is a list of servants that need Evil Bone to perform Ascension and Skill Up.
Rashoumon event (Ibaraki Douji event)
Murder at the Kogetsukan
Inheritance of Glory
Piece of Year 2030 (A Fragment of 2030)
Best Craft Essence: Craft Essence Tier List
Altera (Attila)
Shuten Douji
Aerial Drive
Tower at the End of the World
Device Transfer Guide
Ereshkigal
Arthur Pendragon(Prototype)
Gorgon
Black Holy Grail (The Black Grail)