Defend the Castle

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

Detailed walkthrough
This quests consists of "waves" where a limited number of attackers will spawn and attempt to take over the Castle. Before these waves, the Sole Survivor is instructed to create defenses to protect the Castle. Afterwards, a broadcast from Radio Freedom will ask all minutemen in the area to assist the Sole Survivor at the Castle. Once this is done, the waves will spawn.

Brotherhood of Steel
Waves consists of one vertibird and its occupants which put together, consists of a total of ten vertibirds and about thirty Brotherhood of Steel soldiers. Most of the men inside the ship will not be lootable with the exception of ragdolls falling out.

Institute
Waves of synths and coursers will spawn at various locations. Like the Brotherhood, a large magnitude will also be relayed to the Castle, most often at the southern entrance.

Raiders or Gunners
Waves of raiders and attack dogs or Gunners will attack from either the front side or the back.

Super mutants
Waves of super mutants will spawn with behemoths.

Bugs

 * Many quests involving the Railroad, such as the weathervane, and Randolph quests will automatically fail if not completed beforehand.
 * It is a possibility that Ronnie Shaw's proper dialogue will not appear to end the quest; the only options that will appear are trading and merchant dialogue, leaving the quest unbeatable. There is no known fix for this bug. (It is possible to instantly end the quest by typing the setstage console command: SetStage 000bdb04 450)
 * Sometimes, enemy waves will not move upon spawning or will move in the wrong direction in an attempt to fight other enemies in the area. If the quest appears to be stuck, try looking for the enemy wave nearby, and then drawing them back to the castle. Synths can also teleport into the player character-made structures.
 * It is possible to glitch the quest during the synth attack in such a way that all guns, energy weapons, and explosives including Minutemen artillery will cease dealing damage. From that point on, other characters and the player character may fire or throw grenades at each other to no effect, and only bashing or other melee attacks will deal damage.
 * This quest was meant to also be a repeatable/radiant quest. However, much like with Defend the Artillery quest, looping errors prevented this from occurring.
 * This seems to have been fixed with official patch 1.3.

Verteidigung der Burg Defenda o Castelo Защита замка Захистити Замок