Source of all living matter (Anime)

The source of all living matter is named by Eren Kruger in the episode Attack Titan.

Its first appearance was in Episode #80 and had merged with Ymir Fritz causing her to Transform for the first time by merging with her spine. It created the Founding Titan and passed onto one of Ymir’s children Maria,Rose,and Sina and one of those children inherited the Founding wha’ll the others inherited one of the other 9 Titans.

Abilities
When it merged with the Spine of Ymir it transformed her into the first Titan.

Appearance
It is see through Creature and Glows a Blueish white Hew. It can also stretch to a very long snake like Creature.