Path (Anime)

"It's as if all the Subjects of Ymir are connected by something we can't see. One inheritor said they saw paths. The blood and bones that form a Titan, and at times, even memories and thoughts through those paths. All the paths cross at a single coordinate. In others words, that's...the Founding Titan. Every single Subject of Ymir is connected to that coordinate."

- Eren Kruger explains the secrets of Titans to Grisha Jaeger

Paths (道) are channels that connect all Titans and Subjects of Ymir together.

Overview
The idea of paths came from noticing that the Nine Titans are sent to a random baby among the Subjects of Ymir, regardless of distance or blood relations, if they die without being eaten. This implies that the Subjects of Ymir are all connected by something invisible, and what connects them are called paths.

Paths serve as channels for the transportation of several things, such as, but not limited to, memories and thoughts from other Subjects of Ymir, and the flesh and bones that make up a Titan's body.

Paths also transcend physical space and time, as proven by the fact that Eren Kruger had "memories" of Mikasa Ackermann and Armin Arlelt before they were even born.

Coordinate
When paths cross, the point is known as a "coordinate" (座標). The Founding Titan is the Coordinate where the paths of all Subjects of Ymir and Titans cross. It can alter the memories of Subjects of Ymir, and command all other Titans. However, royal blood is required to access the power; if one is not a royal, it can still be triggered by touching someone, preferably a Titan, who has royal blood.

Unknown land
Although paths are invisible in the physical world, they can be seen by entering an unknown land. There, light-colored soil covers the ground and paths manifest as trails of light in the sky, similar in appearance to an aurora. Ymir entered that land after she gained the power of the Titans.

History
According to Eren Jaeger and Eren Kruger, one of their predecessors saw paths.

During the year 845, after Ymir devoured Marcel Galliard and gained the power of the Titans, she awoke in the unknown land. When she saw the paths in the sky, she called them "freedom" spread out before her. She vowed to live a life without regrets afterward.