To make himself the center of hatred (to end the cycle of hatred with himself) to try to save the Paradis Islanders.
The people that Eren fought for are even more restrictive over his freedom and fate than the monsters that he believed kept him at bay inside the walls of Eldia. Eren no longer views these people worthy of a freedom, hence the Rumbling, but these Eldian revolutionists still make the cut.
With the realization that he could use a royal descendant to gain access to Paths and communicate with Ymir, Eren's goal became clear: to set up a situation where he could release all of the Titans inside the Walls, colloquially known as "the Rumbling," unimpeded.
The Rumbling is an event set off by Eren Yeager that creates multiple colossal Titans, who rampage across the entire Earth. As described by the Attack on Titan Wiki, “The Rumbling was a cataclysmic event involving Karl Fritz's Wall Titans marching across the earth, destroying all life upon it.
Several of his friends died when the Titans invaded Trost. Then, he joined Levi's squad and felt guilty for his comrades' deaths during their battle against the Female Titan. The more friends he lost, the darker Eren's mindset became.
Eren hates Mikasa's supposed lack of free will and claims he always hated her for having no freedom. Eren points to Mikasa's headaches as proof her Ackerman bloodline is all that's keeping them together.
Why didn't Zeke tried to eat Eren and take the founding titan as he already have royal blood? Why didn't he took founding titan from Eren? He already has royal blood. From this he can use the power of Founding titan to it's full extent and achieve his goal.
"The Rumbling" is a single recorded by Japanese alternative metal band SiM, released from the EP Beware through Pony Canyon label. The television edit version of the song was released on January 10, 2022, while the full version was released on February 7, 2022.
Seeing Mikasa's choice, Ymir abandoned her hold over the Founding Titan, ending both the Rumbling and the Power of the Titans.
Eren did plan a lot. He still got surprised sometimes, so I don't think he planned everything. However, he planned enough. We know he orchestrated the massacre of the Reiss family.
The Rumbling was never meant to end the world or stop enemies from attacking. In the end, the Rumbling accomplished Karl Fritz's goal of ending the war. At least ending the conflict between the Eldians and the Marleyans.
2 The Rumbling Killed 80% Of The World
After various difficulties, strategic plans, and devastating deaths, Eren Yeager was finally put to a stop mere days after he commenced the Rumbling.
It was then that Eren realized the hatred for Eldians (especially on Paradis) would never end, and it would be better to just destroy the world leaving only Eldians from the island “that bore and raised him”.
Eren was broken up over Sasha's death, but due to what he has seen and what he has to do to save the Eldians, hearing Sasha's final words broke through to him, reminding him of when they were young and the world seemed more straightforward.
Eren felt that he had no choice but to do all of this because of his Attack Titan power setting fate in stone, and there was a part of him that compelled him to do all of that regardless of how he truly felt about his actions.
Because Eren wanted to end the titans which requires his friends to kill him but if they does that they can't go back to Paradis. So they needs a place. Also without any enemy paradis will get into civil war like they did before.
The Rumbling is only effective for the first 24–48 hours, which is a norm, since humans needs time to gather informations about their opponents. During that time, humans probably testing all their available weapons (excluding nukes), and see which ones are the most effective.
Though Eldia ultimately survived the Rumbling, more than 80 percent of the world perished and the Titans permanently disappeared from the world.
When Zeke died, the needed physical contact between the Founding Titan and the Royal Blood ended, thus stopping the Rumbling.
According to his estimations, there were around 573,084 Wall Titans in the Rumbling.
Eren possessed the power of three Titans. From his father, Eren inherited the Attack and Founding Titans. After eating Lara Tybur during the Raid on Liberio, he gained the War Hammer Titan as well.
The beginning of the Rumbling.
The Wall Titans resemble Colossal Titans in appearance and are between 50 and 60 meters tall. They move in response to the founder titan's commands. These 50-meter-tall mounds of flesh have no independent thought and are entirely under the Founder's control.
Titan shifting power is transmitted by the consumption of spinal fluid. The Titan failed to drink eren and thus never became one of the 9 Titans.
it's most likely that his entire body would transform. and his Titan form would look completely different judging by the other founding Titan users throughout the series his appearance would probably look similar to his attack Titan form with bones protruding from his body similar to Amir.
In this version, Eren and Historia do have a romantic relationship and he becomes the father of her child.