Powerless Shell (無力の殻, Muryoku no Kara?) is a Skill that makes the user difficult to perceive as a Servant, declining one's parameters and suppresses one's Skills.

Rank User(s)
A Henry Jekyll and Hyde (Assassin)
While his mind and body are in the form of Jekyll, it suppresses his Personal Skills, reduces all parameters, and his presence is no longer recognizable or perceivable as a Servant. Conversely, the dangerousness of Jekyll that has his Personal Skills invoked is on the level of a Magical Beast and his parameters explosively skyrocket as if a recoil. In a normal Holy Grail War, it would be a valuable Skill, but in Fate/Grand Order, it is more or less ineffectual.[1]
? Henry Jekyll and Hyde (Berserker)
Servant Skills
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