Individuals specially trained in combat against ghouls, with good physical capacity and usually carrying Quinques, which are very versatile weapons built from the kagunes of the ghouls they capture.
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CCG Investigators Ranking – Tokyo Ghoul
There is a record of many CCG Researchers and allies, so in order not to make a list that is too extensive I will show the most relevant ones:
Shizaru
Half human, half ghoul, capable of dealing with an S ghoul by working as a team with other researchers. He died being Rank 2.
Kureo Mado
An investigator First class who was obsessed with killing ghouls. His range of abilities was around being able to face A or even A+ ghouls.
Yonebayashi
Half human, half ghoul, with an amazing ability to wield her kagune but with very little stamina and strength, because she never trains. The story ends being Rank 2.
Akira Mado
Kureo Mado's daughter, Associated Special Class and a great combatant capable of dealing with some S threats on her own.
Iwao and Shinohara
Two researchers Special class whom we see on several occasions in history, with extensive combat experience and capable of stopping SS ghouls when they use their armor.
Mutsuki
An artificial half-ghoul Investigator who started as Rank 3 and with little power to combat but after an intense stage in which he was tortured by a ghoul, he managed to become much stronger and more serious to the point of rivaling SS ghouls and receiving the position of Special class.
Juuzou Suzuya
Investigator Special class, capable of fighting both Yasuhisa sisters (maybe S threat is that then) at the same time without taking the confrontation seriously. Later, with armor, he is able to face SS ghouls alone.
Urie
Half human, and half ghoul. It evolves throughout history until it is Associate Special Class and be able to deal with SS ghouls.
Houji
A Special class very intelligent, tactical and skilled in combat. He alone, along with his quinque, is capable of handling SS+ ghouls.
Matsuri Washuu
He has not been seen fighting seriously, as he is usually the main strategist and commander of all operations, but he is the grandson of Tsuneyoshi Washuu and half-ghoul, as well as a Special class, being able to deduce that he is very capable in combat.
Koutarou Amon
As a Ghoul Investigator he was able to fight even an SS-classified ghoul (Kaneki), and later being transformed into an artificial ghoul, he remained faithful to justice but obtained the power of a ghoul. SSS.
Kaiko
Arima and Furuta's direct superior, and a member of the V organization. He is capable of fighting several SS ghouls and high-ranking investigators at the same time. It is also understood that he alone defeated Matsuri Washuu.
Tsuneyoshi Washuu
Head and president of the GCC. He has not been seen fighting but it is known that he was able to defeat an SSS ghoul in the past. He was defeated in a fight where his clan faced Uta (SS), Donato (SS), Furuta (SSS) and Kaiko.
Kishou Arima "The angel of Death"
The greatest Ghoul Investigator in history and in turn the One-Eyed King, and therefore, the leader of the Aogiri Tree. He is human but has the reflexes and speed of an artificial ghoul, and is thus able to face SSS threats alone without suffering any damage. Even Tatara bows before him.
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