Operation Babel: New Tokyo Legacy

Story related and cannot be missed. This unlocks upon completing the mission "7H, Geomatrix"

Head to Sakura TV and dispatch to Geomatrix. The first floor is nothing special. On the second floor, at the door, you need to select "Dread" for the first question and "Nought" for the second question to continue.

On the third floor, there will be a sniper. As you approach the sniper, the sniper will shoot you, and you'll take some damage. If you try to approach the sniper again from the same, you will get shot and all members will take 9,999 damage, thus wiping out your party. The trick to this is that you will have to approach the sniper until you get shot with some damage, and go around to the opposite end and then approach him again, and keep doing this until you can safely reach the sniper. You can use some Power Recorders to be on the safe side.

After this, you will fight Dreadnought himself. Dreadnought hits often and hard, so you will be healing a lot. If you somehow have the Range Break spell or item, it would help a lot. Dreadnought can also summon backup Variants if the battle takes too long.