The Fort conversation awards 2 points for saying, "Let's just listen to [Caesar], figure out what he's up to, and get out", 1 point for saying, "I just want to hear Caesar out." and 1 point for saying, "With how messed up New Vegas is, do you really think Caesar has nothing to offer?", followed by, "I'm just trying to be open-minded." It's possible to lose Arcade permanently at this point.
Up to 2 points can be gained by speaking to Thomas Hildern. Arcade will ask the player for his opinion on Hildern. 2 points are gained by saying, "Good thing there are still people like you around." and 1 point for saying, "I'm sure he means well."
1 point can be gained during That Lucky Old Sun, when Arcade suggests that the power should be directed to Fremont and Westside. 1 point is awarded for agreeing with him or by suggesting to divert power to the whole region, and passing an Intelligence 7 check.
1 point for saying, "If you say so. I'm not arguing." when Arcade mentions that he's heard about Anderson.
2 points for completing the quest by blaming the problem on the Scorpions and letting Tom Anderson go.
1 point for completing the quest by getting Tom Anderson to turn himself in with a fake story about fighting over Dazzle, thus letting Westside Co-op continue to siphon the water off from the NCR.
2 points for killing Anderson and passing an Intelligence 7 check by saying, "You're assuming a motive without evidence. Please be rational." when Arcade blows his top, and another by saying "It's cleaner this way, without bringing NCR in. No connecting Anderson back to the locals.".
The quest will not start until the player reaches one of the following storyline milestones:
Arcade will reveal that he has stayed in touch with his father's old squad and suggest that their firepower can help tip the battle against the Legion. He will ask the player to the remaining squad members, the Remnants. These are:
If the player asks them to fight for the NCR, Moreno will leave in disgust. He will don his armor and declare that he won't do it at all. The player can convince him to fight with a high NCR infamy or a Speech check of 80.
Selecting the Legion will result in Kreger, Johnson, and Arcade abandoning the Courier permanently.
Upon exiting the bunker, Arcade will meet the player, wearing his father's Tesla advanced power armor and ask for guidance: Should he pretend to be his father and fight alongside the Remnants at the Dam? Or trust his instincts and help the people of Freeside during the battle? The player's choice determines his ending.
Completing this quest will result in the Enclave remnants fighting for the chosen side at the battle.
If they fight for the NCR, they will deploy at the rim and engage a contubernium of up to six prime legionaries and centurions. Kreger and Moreno (if present) will hang back, while Doctor Henry and Cannibal Johnson will assist the player all the way up to the Legate's camp. If Brotherhood of Steel Paladins and Knights assist the Republic, they will not be hostile to the Enclave.
If they fight for the Legion, only Moreno and Henry will deploy and attack the NCR troops.
If the player suggested that Arcade fight at the dam, he will present in the visitors center, assisting two heavy troopers.
With Arcade, convince the Remnants to reunite for one last battle.
Ask Doctor Henry to come to the Remnants reunion.
Ask Daisy Whitman to come to the Remnants reunion.
Ask Cannibal Johnson to come to the Remnants reunion.
Ask Orion Moreno to come to the Remnants reunion.
Ask Judah Kreger to come to the Remnants reunion.
Gain access to the Remnants Bunker.
Ask the Remnants to support the fight against the Legion or the NCR.
(if you chose to help NCR) Try to convince Orion Moreno to stay.
(if you chose to help NCR) Tell Judah Kreger what happened with Orion Moreno.
(if you chose to help NCR) Acquire Power Armor Training from Daisy Whitman.
(if you chose to help Legion) Acquire Power Armor Training from Orion Moreno.
Leave the Remnants' command room so they can plan for the coming battle.
PC To find out how many positive points the Courier had acquired with Arcade, use the console command show "16117f".nArcadeLike.
PC Likewise, to find out how many negative points the Courier had acquired with Arcade, use the console command show "16117f".nArcadeDislike.
Behind the scenes
The name of the quest is from the poem and song "Auld Lang Syne", traditionally sung on New Year's Eve. The title can be loosely translated from Scottish as "For Days Gone By", or "For Old Time's Sake", referring to remembrance.
It is possible to complete the quest, without losing Arcade as a permanent companion. If he's told to wait at the Lucky 38 after recruiting the Remnants, but before entering the bunker, he will remain there upon return. Doing so breaks his scripts, however, and no ending will be displayed for him and the player will miss out on the power armor. The only ending available will be to sell him into slavery during Et Tumor, Brute?
PCXbox 360 The Remnants can randomly turn hostile at the Dam if the player sides with Mr House or Yes Man.
PlayStation 3 Receiving the power armor training from the Brotherhood can break the script for the quest, skipping over dialogue that awards the player Daisy's power armor.
Xbox 360 The script to unlock the briefing room at the end of the quest can misfire and not unlock it after dealing with Moreno. The player can steal it from him to open it.