The first part of the plan was fairly simple. Sow as much chaos as possible, and disturb the enemy lines, while causing destruction.
One of the Angelic Order's member had infiltrated the enemy command center during the previous day and they learnt the larger parts of the enemy battleplan. Also, they managed to acquire the soldier placements of each unit of evolved.
From there they learnt a lot of important information, which would determine the movement of their own army.
For example there were three main artillery stations at the east side of the wall. During the night these were places where they put one of Frank's bombs.
Outside the alarm still screamed and people's shouting echoed down the street. The ceiling rumbled as large vehicles moved along the road. These were the self-propelled artilleries and tanks. Taking them out will be the Ouroboros Cohort's first objective.