In his battle against the War Hammer Titan in Marley, Eren displays a terrifying mastery of his power. He transforms multiple times in quick succession, using his Titan form as a weapon of mass destruction and strategy rather than just a brawler.
Eren transforms to fight the Female Titan (Annie Leonhart) in the forest. This is the first time he utilizes combat skills while transformed, though his rage nearly overtakes his control. when does eren turn into a titan
While inside the Titan's stomach, Eren witnesses his comrades being digested alive. The sheer combination of his desire to live, his rage toward the Titans, and the horrific trauma triggers his dormant Power of the Titans. He transforms into a Titan for the first time from inside the Titan that ate him, ripping his way out and going on a rampage. This was the audience's first hint that Eren was not an ordinary human. In his battle against the War Hammer Titan
Analysis of Eren Yeager’s initial and notable Titan transformations. This is the first time he utilizes combat