Ninjutsu (忍術, Ninjutsu?) is the general term for the secret intelligence techniques, combat techniques, larceny techniques, torture techniques, etc., employed by ninjas. Its system differs between each school.

Rank User(s)
At least A+++ Koga Saburo
Dorothea Coyett claims that he is known for being the strongest.
A+++ One stands shoulder to shoulder among the legendary ninjas.
Fuuma Kotarou
The system is unique for each school, and almost no documents related to the Fuma shinobi clan, brought to ruin by the Tokugawa house, are left behind.

This Heroic Spirit, fifth head of the clan, is thought to be chosen by means of his true strength and competency.[1]

A++ One can be said to be the equal of the heads of the Iga and the Koga.
A Katou Danzou
Since Kato Danzo was loaded with the skills of (the First) Fuma Kotaro, her school would be that of the Fuma ninjas.
Mochizuki Chiyome
A general term for the different skills used by ninja, such as spying, stealing, torture, and battle techniques. Since she was born as the head of the Mochizuki Clan in the Alliance of the 53 Houses of Kouga, she possesses rank A in this skill.[2]
  1. Fate/Grand Order material IV — Profile of Fuuma Kotarou, translated by castor212 at Beast's Lair.
  2. Fate/Grand Order material VI — Profile of Mochizuki Chiyome, translated by BananaShiki at Reddit.
Servant Skills
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