The Sole Survivor must go to the gang leaders' locations and execute them: Nisha will be in Fizztop Mountain, Mags and William Black will be in The Parlor and Mason will be in Bradberton Amphitheater. The player character can execute them in any order, but once one of the leaders is killed, all the raiders in the park will become hostile to the player character, including Shank. This will involve a lengthy battle to clear Nuka-Town USA of all gang members, which involves killing eighty or more named and unnamed gang members in total. In addition to each gang's base of operation, the player character will also need to clear out Cappy's Cafe and Nuka-Town market of any raiders there. The optional objective to restore power to Nuka-World power plant may be done at any time. After all the leaders are dead, speak with Mackenzie Bridgeman again to complete the quest.
While members of The Pack, Operators and Disciples will no longer spawn in Nuka-Town USA, they will continue to spawn in small groups at various points around Nuka-World while battling other enemy NPCs.
If not killed, Porter Gage will remain in-place at the Fizztop Grille after completion. While he won't turn hostile, the player character will not be able to interact with him in any way.
Though the quest does not directly lead to restoring power to Nuka World, completion unlocks the door at the Nuka-World power plant allowing the Sole Survivor to restore power.
Completing this quest immediately after Taken for a Ride and then restoring power at the Nuka-World power plant opens up all areas of the park for exploration, eliminating the need to return later.
If any of the parks have been assigned to any of the raider gangs prior to completing this quest, those areas will remain under the control of those gangs and will remain hostile to the Sole Survivor after completion of this quest.
Any settlement assigned to a gang will also remain under their control, however after killing all the members present it can be converted back to a standard settlement. This includes the Nuka-World Red Rocket.
After completion, the traders and slaves around Nuka-Town USA will have different dialogue, often thanking the Sole Survivor for freeing them or commenting on how much better things are now that the raiders are gone.
Killing unnamed raiders throughout the park will not turn all raiders hostile, so long as the player character remains "hidden" and the act is not witnessed.
pcxboxone If completed before starting any quests given by Porter Gage, he will stand idle on top in the overboss's room, and will not provide any dialogue unless he is engaged in combat.[verified]
pcps4xboxone After completing the quest, leaving Nuka-World, and then coming back, all of the traders will unequip all of their inventory items, including any clothing, instead of only their explosive collar. It is still possible to trade with them.[verified]
pc This can be fixed by using the console command OpenActorContainer 1 and re-equipping their clothing through the trade menu.
ps4 If one completes this quest after building any raider settlements, they may be unable to clear the raider settlements if the settlements contain turrets. The turrets will be indestructible, staying alive at 1 HP, but attempting to use the workshop will give a message instructing the player character to first clear the area of all enemies, even though all raiders are killed. Reducing the health of all turrets to minimum and then leaving the area and later returning will reset the turrets, making them friendly again.[verified]
pc When entering the market and killing the raiders there so that the Sole Survivor can talk to Mackenzie, she and most of the other NPCs will continue to cower even after all the enemies are gone. The only way to engage Mackenzie in dialog is use the console to disable and re-enable her.