Founding Titan (Anime)

"Frieda's Titan was superior to all other Titans. You could say her Titan had unsurpassable power."

- Rod Reiss claims the Coordinate is the strongest Titan power

The Coordinate (座標) is the ultimate Titan power that was once in possession of the Reiss family, who passed it down from generation to generation. Its screams can alter the minds of both humans and Titans, but in the case of the former, some bloodlines are exempt from its power. It is currently in the possession of Eren Jaeger and is sought over by the Warriors.

Abilities
The Coordinate's power is used by screaming. Whoever has the Coordinate does not have to transform in order to use its abilities, and the screams of a human would suffice. Furthermore, the screams do not have to be loud or even "screams": Frieda Reiss was able use the memory alteration ability by casually talking, although her target was only Historia who was right in front her.

Titan control
The Coordinate enables its wielder to control the Titans by screaming. It has been observed that Pure Titans simply obeyed the orders given by its wielder while Intelligent Titans can sense its use, though they are seemingly not influenced by its control. It is similar to the Female Titan's ability to attract Titans by screaming.

Memory manipulation
The Coordinate's screams also affect humans, but not every human is affected by this ability. The King once used this ability to make humanity inside the Walls forget about the past, except a few minority bloodlines. Frieda used this ability to make Historia forget about her, but these memories resurfaced when Historia touched Eren Jaeger, the current Coordinate.

History
The true royal family of humanity, the Reiss family, used the Coordinate's power to alter the memories of humanity inside the Walls so they can be controlled. At one point, the King made everyone inside the Walls forget about the past. The Ackermann family and the Oriental clan were unaffected by this power and turned against the King's ideology. Fearing the inability to control them, the King prosecuted both bloodlines to near extinction.

The Fall of Shiganshina arc
After the Fall of Wall Maria, Grisha Jaeger goes to the Underground Chapel where the Reiss family is and transforms into a Titan. Frieda Reiss also transforms and battles Grisha, but loses and is eaten. Grisha obtains the Coordinate and then proceeds to kill every single member of the Reiss family, except Rod Reiss who escapes. He later finds his son Eren and injects him with some kind of serum, turning his son into a Pure Titan. Eren eats Grisha and becomes the new Coordinate.

Clash of the Titans arc
Before fleeing the Scouts in the Forest of Giant Trees, Reiner states that the connections between the Reiss family and the Order of the Walls make Historia Reiss a valuable asset for the Warriors' mission, and having her with them will make their goal much easier if Eren Jaeger is not the "Coordinate" they are searching for. Later that day, the Warriors' suspicions are confirmed when Eren unleashes the Coordinate, striking the hand of a smiling Titan, screams, and causing all the surrounding Titans to swarm it and tear it to pieces. When Reiner and Bertholdt approach him afterward, Eren's outburst once again triggers the Coordinate and sends the nearby Titans rushing towards the Warriors, allowing for the Scouts to escape. On the journey back to Wall Rose, all Titans encountered ignore the Scouts and instead run in the Warriors' direction under Eren's subconscious orders.

The Uprising arc
A squadron from the Military Police led by Kenny Ackermann kidnaps Eren Jaeger and Historia Reiss and brings them to Historia's father, Rod Reiss. After reading a note from Eren on how Ymir got her Titan powers, Hange Zoë theorizes that the government is planning to devour Eren to gain his power.

Eren awakes, chained up and gagged, in the Reiss family's Underground Chapel, where the power has been passed down for generations.

Trivia

 * Frieda Reiss normally had blue eyes, but when she transformed into an Intelligent Titan, her eyes glowed purple. When Grisha Jaeger devoured her and obtained the Coordinate, his normally green eyes turned purple as well.
 * The Coordinate's power is extremely similar to the Beast Titan's ability to control Titans, which he also uses by screaming or talking.

Navigation
Koordinate (Anime)