This page of our Control guide contains a walkthrough for a side quest called A Good Defense. You will learn, e.g. how to go through the training course within the time limit and how to unlock the Shield skill.
To begin the quest, you need to pick-up a document found very close to Central Maintenance and Access Corridor. Go to the Maintenance - the documents are marked in the picture above.
Walkthrough: Your task is to get through whole Field Training section in the given time. The task requires great precision and speed. It is good to destroy shields quickly, without excessive aiming, preferably while running. The area has several rooms in which you will have to shoot, jump, or use telekinesis to insert batteries into place. After several attempts, you will learn the placement and easily complete the task. If the course still continues to be problematic, master Evasion (A Merry Chase side quest) which will greatly speed up your character.
You will be taken into the astral plane, unlocking Shield - a very useful skill. Thanks to it, Jesse can protect herself from attacks. Use the Shield to block. With it, you can avoid enemy attacks and get to the end of the stage. You will be rewarded with materials, modifications and 4 skill points.