Attack on Titan - Season 2, Episode 12: Soundtracks

The armoured titan started throwing away all the mindless titans that clung to him. Meanwhile, on the other side, Hannes attempted to slay the smiling titan. Eren failed to transform.

Looking at the hopeless situation, Mikasa made a confession to Eren. Eren then stood up and tried to punch the smiling titan. This was played again when Ymir left Historia.

Eren awakened his "coordinate" power.

Played at the end of the episode. A new character was revealed.

Historia rides Ymir as Hannes fights the Titan that killed Eren’s mother