Defend the Castle

Defend the Castle is a main quest involving the Commonwealth Minutemen, in Fallout 4.

Synopsis
With revenge fresh in the air, the Minutemen and their general are at the final threshold, where the remnants of their enemies are preparing for a final push to wipe the Castle and its inhabitants off of the map. Can they survive the waves after waves, or will they fall again, just as they had before.

Walkthrough
This entire quest consists of various waves, in which the Sole Survivor and the Minutemen, as well as any settlers at the Castle, will have to defend the stronghold against a multitude of various enemy factions.

Brotherhood of Steel
The first waves that will clash against the Castle's walls, consists of around a dozen vertibirds, and the shock troops that they drop off, both inside and outside of the Castle. After the Brotherhood of Steel's remnants have been dealt with, reinforcements will finally drop off, and the Minutemen will gain a few moments to regain their strength.

Institute
After the Brotherhood of Steel have been dealt with, a group of generation 1&2 synths, as well as their courser masters, will begin teleporting in at various locations around the Castle. Unlike the Brotherhood of Steel, these waves are rather unpredictable, as the synths can come in from any direction, and have a tendency to flank the defenders. The final wave will include an extra courser, and after they have been dealt with, the synths will finally stop teleporting in, giving the defenders a bit longer than before to prepare for the next attack.

Raiders or Gunners
Randomly determined, and only after the synths have been dealt with in their entirety, waves of either generic raiders and their attack dogs will begin rushing the entrance, or the Gunners will begin attacking from both the entrance and the back door. These waves taper off rather quickly compared to the other two factions, and allow for a bit more breathing room before the final faction attacks.

Super Mutants
The final waves will consist of the super mutants, all of which will be reinforced with behemoths. These waves will only attack from the entrance, and once they have been dealt with, the safety of the Castle and the Minutemen faction can finally be considered safe, for the time being.