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Eren's form of the Founding Titan is called Doomsday Titan ( 終尾の巨人 Shūbi no Kyojin ?).
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Only Eldians containing royal blood are able to use its abilities however, as shown when Eren screamed and punched Dina Fritz's Titan, a member of non-royal blood is capable of using the Founding Titan's ability via physical contact with a member of the royal family. Its screams can affect humans as well, altering their memories, but certain bloodlines are unaffected. The Founding Titan ( 始祖の巨人 Shiso no Kyojin ?) has the ability to control Titans with its screams.The number was reduced again years later when Eren Jaeger's Attack Titan consumed Lara Tybur's War Hammer Titan, bringing the number of Titans down to seven. This resulted in the number of Titans being reduced from nine to eight. The Reiss family would later lose their Titan to Grisha Jaeger after Grisha's Attack Titan ate Frieda Reiss's Founding Titan, the two Titans mixed into one. They distributed the Titans they had among Eldians loyal to them known as warriors. Marley seized control over seven of the Nine Titans during the war, with only the Founding and Attack Titans escaping their grasp. He erased the memories of the Eldians on the island, except for a few minority races which were immune. The King fled and moved many Eldians onto Paradis Island, where he erected three, central Walls.
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When the 145th King inherited the Founding Titan, he abandoned his duties of balancing the continent's powers, leading to the Great Titan War between the other eight Titans. The Nine Titans fought each other in the Great Titan War The Nine Titans soon destroyed the ancient nation of Marley and conquered the entire continent to build the Eldian Empire. Eventually, the powers would split further into the individual Nine Titans, which were subsequently inherited by nine of her descendants. Thirteen years later, she died and her power was then divided between her three daughters who had been forced by their father to consume her remains. Around 1,820 years ago, Ymir Fritz obtained the Power of the Titans and became the first Titan, the Founding Titan.
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