FATE/GRAND ORDER ABSOLUTE DEMONIC FRONT: BABYLONIA - INITIUM ITER

The story focuses on the background of Mash Kyrielight and Romani Archaman, and the events leading up to the Seventh Singularity, Absolute Demonic Front Babylonia. This episode aired on August 3, 2019 at Fate/Grand Order Fes. 2019: Chaldea Park. It was available for download on the Fate/Grand Order mobile app, from August 4, 2019 to August 11, 2019. — Description from AniList community (anilist.co).