The Battle of Shiganshina District was a battle between the Scout Regiment and the Warriors of Marley within the ruins of Shiganshina District, in which Wall Maria was reclaimed five years after its fall and the truth of the outside world was discovered in the basement of Grisha Jaeger's home.
Prelude: In the two months following the coup d'état against the old Royal Government, the military-run government had begun to make great technological advancements after retrieving the contraband obtained by the Military Police Regiment Interior Police. With these findings, the Scout Regiment was able to develop the "Thunder Spears", explosive weapons compatible with ODM gear designed with the purpose of dealing heavy damage to the Armored Titan, whose location following the Wall Rose invasion had become unknown. Additionally, the glowing crystals discovered in the underground cavern beneath the underground Reiss chapel served as an energy-efficient light source, drastically increasing productivity and providing a means for the Scouts to plot a new course to Shiganshina District under the cover of night.
The battle: By sunrise, the Scout Regiment had arrived in Shiganshina District. As planned, all of the Scouts pulled their hoods over their heads to disguise their features. After scaling Wall Maria, 100 of the soldiers made a rush for the outer gate of Shiganshina in order to hide Eren Jaeger's position within their numbers.
Early conflict: By sunrise, the Scout Regiment had arrived in Shiganshina District. As planned, all of the Scouts pulled their hoods over their heads to disguise their features. After scaling Wall Maria, 100 of the soldiers made a rush for the outer gate of Shiganshina in order to hide Eren Jaeger's position within their numbers.
The Armored Titan: The Beast Titan and the Armored Titan quickly began the battle, acting in unison. While Reiner climbed Wall Maria to approach and kill the horses on the other side, the Beast Titan commanded a horde of 2 - 3 meter Titans to charge the structures just to the north of Shiganshina where the Scouts' horses were standing by. Prioritizing the horses' safety, Commander Erwin sent Squads Dirk and Marlene to group up with Klaus at the north gate to defend the horses while Squads Hange and Levi confronted the Armored Titan with their newly designed Thunder Spears.
Source: Battle of Shiganshina District (Anime), available under CC BY-SA 3.0.