1 - Shingeki No Kyojin Ova - Episode

The episode follows two parallel timelines: the present search by the Scout Regiment and the past account written in a diary.

During the 49th Exterior Scouting Mission, Hange Zoë is obsessed with capturing a Titan for research, despite Commander Erwin Smith’s refusal due to the high risk. While pursuing a Titan into a forest, the scouts find the decapitated body of a soldier, Ilse Langnar , hidden inside a tree, with her notebook nearby. Shingeki no Kyojin OVA - Episode 1

The episode introduced the name "Ymir" long before its significance was fully explained in the main series, hinting at a deeper history behind the Titans. The episode follows two parallel timelines: the present

The discovery of the notebook and the evidence that Titans might be sentient changed the Scouts' approach, finally convincing Erwin to allow Titan capture missions. Watch Information The episode introduced the name "Ymir" long before

This was the first time in the series a "mindless" Titan was shown to have the capacity for speech and complex emotion (reverence).