Screaming activated many abilities of the Founding Titan. These abilities could not be used by the Founding Titan’s inheritor. Human screams were sufficient. The screams didn’t have to be loud or in the most literal sense. Frieda Reiss used her memory-altering ability by talking casually, even though Historia was right in front.
Founding Titan Creation
The Founding Titan was able to transform Subjects of Ymir in colossal titan. It could even make them as large as the Colossus Titan. Karl Fritz used this ability in order to create the Walls’ thousands of Colossus Titans. Eren Yeager was able to use this ability in an even greater way. He quickly manifested many past incarnations and controlled them to attack him.
Zeke Yeager’s Beast Titan was capable of transforming Subjects of Ymir to Titans by shouting after injecting the beast’s spinal fluid into them.
Titan control
Mikasa is protected by Eren, even though Eren doesn’t know it. The Founding Titan gave its user the ability of controlling tobacco titan philip by shouting and making them follow almost any order. Eren Yeager demonstrated this by commanding nearby Pure Titans, unintentionally, to eat Dina Fritz’s Titan and attack Armored Titan. Although it was only effective for Pure Titans, those with the power to the Titans may still feel its influence.
Karl Fritz used it to build the Walls. He commanded many Colossus Titans who were forced to harden themselves and live in the Walls. This ability was used by Eldia to command an army Titans for war in ancient times. However, once they were freed, the Titans would become indiscriminate weapons to mass destruction that would kill Eldia’s adversaries.
Although this ability was not known to have any range, Karl Fritz used it in commanding Colossus Titans that covered large swathes of Paradis Island. Rod Reiss stated that the power could wipe out all Titans if it is used to its full potential.
The Founding Titan could alter the minds and memories of entire populations, including whole populations. This ability is related to remember the titans control: Erwin Smith noted that Titans are just transformed humans (specifically the Subjects of Ymir); therefore the screams which control the minds of the former should also be able to affect them. Karl Fritz used it to make Subjects of Ymir forget the history of the world prior to the Walls’ installation. Frieda Reiss also used it to erase Historia’s memory of her visits. These memories were accessible to Historia in dreams. Historia was able to sometimes dream about Frieda’s encounters, but she would forget them when she awoke. This ability was not available to members of the Ackerman family or anyone else who isn’t Subject of Ymir.
The Founding Titan could alter the body composition of any Subject in Ymir. This power was used 600 years ago by an Eldian king to make Subjects of Ymir immune from a widespread epidemic
Zeke Yeager wanted this ability to make all Subjects in Ymir sterile so that they could die in a generation. This would eliminate the Titans from the world once and for all.
The Founding Titan had a height of approximately 13 m. His Founding Titan body was several magnitudes larger than the Wall titan gasoline tanks.
Telepathic Communication
Through the paths they are connected to, the Founding Titan was able to telepathically communicate with all Subjects of Ymir. This ability allowed Eren to communicate with all Subjects of Ymir, allowing him to announce his plans for the Rumbling around the World.
Clairvoyance Founding Titan
The Founding Titan has a future memory inheritance ability similar to the Attack Titan that allows future inheritors to receive future memories or relay their memories to past inheritors. However, it can do more to directly affect the past and preserve the history as it is. It allows inheritors to see time in non-linear ways, allowing them to simultaneously see the future, present and past.
It has a downside: it makes users think incoherently and allows them to follow the flow of events, even though it would be against the will. Eren discusses the disadvantages of this ability with Armin when he speaks to Armin in the realms of paths. He sadly reveals that he used it indirectly to cause his mother’s death by influencing Dina Fritz’s Pure tobacco titan philip morris not to ignore Bertolt, and instead head to Shiganshina.