Board Thread:Manga/@comment-34196931-20200608155101/@comment-36307699-20200611115905

Linense wrote: Your last opinion is very interesting, but if Eren could do that to Zeke, why hasn't he done it with the other changing titans (at least, with the enemies named Reiner, Pieck, Annie and Falco)? This would ensure that no one intrudes on the Rumbling. Perhaps during the attack on Shiganshina Dristrict by Marley, Eren Yeager couldn't be able to turn those titans back into humans. Eren Yeager probably wasn't expecting the invasion so soon. He probably plan on having Zeke Yeager to meet him at Shiganshina. And then, trick Zeke into allowing Eren full access of the Founding Titan powers without any interference. However, Eren did not anticipated that Marley would attack and target him with everything they got. It would have drained a lot of his power by fighting them and getting injured (Gabis' sharpshooting) before coming into contact with Zeke Yeager.

After Eren Yeager finally acquires full access to the Founding Titans' power, he must be running on fumes. With little power he has left, Eren Yeager heals himself, unleash the rumbling and communicate towards every Subjects of Ymir everywhere. Plus, not only does he has full access with the Founding Titan, Eren Yeager probably now have total control of his Attack Titan power as well. With the Attack Titan special power, Eren Yeager probably saw something. He probably saw the alliance between Survey Corp and Marley Warriors, and that they are planning on stopping him.

Eren Yeager probably saw this alliance as a threat that could perhaps destroy Paradise and wipeout all Eldian kind, from his POV. In a weaken state he is in, Eren Yeager summons enough strength towards creating somekind of diversion to divert the alliance away from him. That diversion would be Zeke Yeager turning into the massive titan, and then directs him towards Marley. It would give Eren Yeager more then enough time to recuperate and regain his strength before proceeding towards another objective.

As for the Marley Warriors who still can turn into titans at will. It is proabably part of Eren Yeagers' plan to allow them use their powers until they reach Marley. Once there, Eren Yeager would spring some kind of trap and perhaps steal their powers just as they try to do it towards him.

That is my theory so far. What do you think?