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
5 Star Servants Tier List: Best Servants [5/9 updated!]
Device Transfer Guide
FGO Reroll Tier List [5/11 updated!]
Fate/Apocrypha Event: Inheritance of Glory
Best Servants [★4]: 4 Star Tier List
Tamamo no Mae
5th Singularity: E Pluribus Unum
Anastasia Nikolaevna Romanova
Seal Designation Enforcer