That Lucky Old Sun

 is a side quest in Fallout: New Vegas. It is also an achievement on the Xbox 360 and PC, and a bronze trophy on the PlayStation 3.

Quick walkthrough

 * Talk to Fantastic and Ignacio Rivas and get their passwords.
 * Use the two reflector control terminals outside to connect to the HELIOS One mainframe.
 * Get to the mainframe and repair its electronics.
 * Choose where to distribute power and whether to arm the ARCHIMEDES defense system and wipe out the NCR or not.
 * Get outside and initiate reflector retargeting from the console.
 * OPTIONAL:Get back to Ignacio Rivas for your reward.

Initiating the quest
At the entrance on the south side of Helios One is an NCR officer named Lt. Haggerty, who is the head of the NCR detachment guarding the plant. The player can ask her for access to the plant. She is inclined to turn the player away, but the player can convince her otherwise via several options:
 * Speech 30 - Lie and say the player's brother works there.
 * Science 30 - Point out that the tower isn't working right, and offer to help.
 * If the player's NCR reputation is more positive than negative, or with Speech 35 or more, the player can claim to be with the NCR and be let in.
 * Have an NCR disguise.

Once the player has convinced her, she tells the player to talk to the "idiot wearing sunglasses".

Optionally, the player can sneak in through a back door with a very easy lock (player loses karma). From there the player should find the idiot with the sunglasses, Fantastic, and talk to him to begin the quest.

Fantastic
"They asked me how well I understood theoretical physics. I told them I had a theoretical degree in physics. They said 'welcome aboard'."

In the back of the plant is a science lab of sorts, where Fantastic and Ignacio Rivas are trying to get the output of the plant up. Fantastic is a transparent fraud who clearly has no idea what he's doing. Rivas is an actual scientist, but is really working for the Followers of the Apocalypse, who worry that the plant is not merely a power plant, but a pre-War super weapon. As it turns out, it is.

Fantastic and Rivas explain that to get the plant running, the remote mirror control systems need to be connected to the mainframe, and then the mirrors retargeted from the mainframe terminal in the plant itself. The two mirror control terminals require a password. Each man holds a password for one of the two mirror control terminals. Fantastic will give his up easily enough, but Rivas will only give the player his if the player gains his trust by professing to be peaceful (or at least not violent), has the Confirmed Bachelor perk, or if the player claims to be with the Brotherhood of Steel. The player can also pickpocket the password from him, or a duplicate password can be found in a second floor office, lying on a desk. Note that Fantastic's password is not in his inventory; it must either be obtained via dialogue or found in the same room as Rivas's password in a footlocker on the second floor.

The outside terminals
Both terminals are inside small shacks on the outer perimeter of the mirror field. The west mirror control terminal requires the password obtained from Fantastic. The east one can be unlocked with the password obtained from Ignacio Rivas or from the office of the main building on the second floor by the room with the giant hole in the floor, or is hard locked and can be hacked with 75 Science.

The western shack has multiple traps, including three frag mines, a rigged shotgun with a tripwire, and two bear traps. Once the traps have been disarmed or avoided, the terminal just needs to be activated and "Reset Mainframe Connection" selected.

This second terminal is protected by several NCR guard dogs but they aren't much of a problem. you activate it just like the first, via selecting "Reset Mainframe Connection".

Get to the mainframe
The player then enters the tower via a door near the base. Just past the door and a short hallway is an area with multiple turrets and hostile robots. In a room just across from the entrance is an easy locked terminal that can shut off the turrets, or make them attack the robots indiscriminately. (Warning: there are four live frag mines in the room with the terminal.) The player then must wind through the rest of the building, destroying many robots along the way, until arriving at an elevator in the basement that takes the player to the observation level. Along the way it is handy, but optional, to get a Poseidon Energy employee ID card, of which there are two, both lying on the floor in a room adjacent to the room with the elevator. There is a door in the elevator room with an average lock that leads to the room with the IDs, or the player can go back through a room filled with protectrons and down a hall to reach the back door of the room.

Repair the mainframe
The observation level contains not much more than the mainframe itself and stairs to reach the exit door to the outer viewing deck. The mainframe is not working, as it doesn't have enough power because the attached generator is malfunctioning. The player can either repair the generator with a piece of scrap metal and 35 Repair, or can go up the stairs to find a maintenance bot called Python, which can be activated with a Poseidon Energy employee ID card or with 45 Science skill. Once activated, the robot will repair the mainframe.

Choose a Side
The terminal on the mainframe contains some notes the player has probably already seen on previous terminals in the building, and an option Configure Power Grid. Selecting it reveals 5 options:


 * 1) McCarran and Las Vegas Strip: By directing the extra power toward Camp McCarran and the Strip, the power will be transferred to the NCR home states along with the energy generated at Hoover Dam and part of it to power the neon lights in the casinos in New Vegas. You will gain NCR fame for making this decision.
 * 2) Fremont and Westside: This solution  will direct all the power toward the two poorest areas in the New Vegas area and the FOA camps located there. This pleases the Followers of the Apocalypse, though it won't benefit as many people as it potentially could.
 * 3) Full region: The 'best' solution. The energy will be distributed to the entire regional grid equally, but as a result everyone will only get a small amount of energy and the plant will suffer frequent brownouts. You will gain a large amount of Followers of the Apocalypse reputation and Ignacio Rivas will give you a Big Book of Science, 3 stimpaks and 2 doctor's bags as a reward for making this decision.
 * 4) ARCHIMEDES II: This solution diverts power to the next-generation space laser system mentioned in the terminal notes and will give the player the option of calling down space-laser strikes once every twenty four hours (Patch Update), provided the player has also obtained Euclid's C-Finder. The Followers are satisfied with this option, as Ignacio Rivas does not know the location to which the power has been diverted. However, Ignacio will not give you a Big Book of Science as part of your reward.
 * 5) Full region (emergency output level): This solution overloads the plant, which prevents Archimedes I from being activated (see further notes). This gains no reputation with any faction, but Ignacio Rivas will still give the player some rewards.

Once one of the five options has been selected, the terminal returns to the main menu. A new option comes up at this point, Arm ARCHIMEDES Plant Defense System. If it is activated, then the Archimedes I plant defense system will be triggered as soon as the player activates the Reflector Control Panel on the outside of the tower. Doing so will call down a laser strike on the area around the plant (unless power option 5 was selected), killing all the NCR personnel in the area. The result will be massive infamy gain with the NCR and no rewards from either Fantastic or Ignacio Rivas, even if the power is diverted to their preferred location. (It is a nifty sequence, so choosing it at least once is recommended, even if the player chooses to reload a previous save game afterward.)

Until the choices are locked in by activating the Reflector Control Panel, the status of the Archimedes I defense system can be changed and the options for where the power goes can be changed.

Time to flip the switch
Once the player has chosen the final power grid disposition and whether to activate Archimedes I, the final step is to go up the stairs and through the door to the outside of the tower. The Reflector Control Panel is down a spiral ramp to the left. It can only be activated between 9 am and 3 pm. Once the player activates the control panel, one of three things will happen:
 * If the player has chosen to activate the Archimedes I defense system, and has chosen option 5 (overload) for the power grid, horns will blare and a warning will play about the imminent weapon test, but shortly thereafter everything grinds to a halt. If the player is trusted by Ignacio Rivas, they can now go talk to him to receive awards. Otherwise the quest ends.
 * If the player has chosen to activate the Archimedes I defense system, and has chosen any of options 1-4 for the power grid, the horns blare and warnings sound, and this time everything works perfectly. All of the NCR troops in the area of the plant (inside and out) are obliterated in a massive display of pyrotechnics. The quest ends and the player gains NCR infamy. Fantastic and Ignacio Rivas will not have been killed, but will refuse to talk to the player. If the player goes away for two days after this and returns, the plant will be occupied by Caesar's Legion, who have stepped in to fill the void.
 * If the player has not chosen to activate Archimedes I, but has chosen any power grid option, the plant powers up.
 * If the player chose anything other than option 1, and is not trusted by Ignacio Rivas, the quest will end.
 * If the player selected option 1 (McCarran and the Strip), they can talk to Fantastic, who will be thrilled, claim all the credit, and give the player nothing. The player will gain a lot of NCR reputation.
 * If the player selected option 2 (Fremont and Westside), and are trusted by Ignacio Rivas, they can talk to him to get 3 stimpaks, 2 doctor's bag, and a moderate amount of Followers of the Apocalypse reputation.
 * If the player selected option 3 (Full Region), and are trusted by Ignacio Rivas, they can talk to him to get a Big Book of Science, 3 stimpaks, 2 doctor's bags, and a large amount of Followers of the Apocalypse reputation.
 * If the player selected option 4 (Archimedes II), and are trusted by Ignacio Rivas, they can talk to him to get two stimpaks, a doctor's bag, and a small amount of Followers of the Apocalypse reputation. Apparently they're just happy the NCR isn't hogging all the power.
 * If the player selected option 5 (Full Region, Emergency Output Level), and are trusted by Ignacio Rivas, they can talk to him to get 3 stimpaks, 2 doctor's bags, and no reputation gain.
 * No matter how the quest ends, the player gains 585 XP.

Bugs
- Even after the 2011 updates, this glitch still occurs.
 * After activating the control panel, and the screen goes blurry, the blur will increase in some circumstances, such as dialogue mode, grenade impact blur or trading mode, a simple restart of the game will fix this.
 * If Fantastic is killed before the power is restored, Ignacio Rivas may not provide the quest-ending dialogue option after powering up the plant (quest cannot be completed).
 * When the player sets the power to Full Region (Emergency Output Level), then tells Ignacio that "I overloaded the plant. No one will be able to use it to power a weapon.", the option will stay and can be used over and over to get XP and loot.
 * Sometimes the quest finishes with no rewards, even if the player didn't activate Archimedes I.
 * It is advised that you tell ED-E to wait outside of the Helios One tower, as it is possible for him to get stuck in the pipes on the ceiling in certain places.
 * Sometimes do not get the lockpick and/or terminal interface when trying to lockpick or hack terminals.
 * If you are doing the NCR quest chain and go to Hoover Dam to talk to the Commander before you finish That Lucky Old Sun, Fantastic will be there instead of Helios One, meaning it is impossible to finish if it tells you to talk to Fantastic. Sometimes, it actually seems to work to go to the Hoover Dam and simply kill Fantastic to complete the quest. The guards will not get hostile if this trick works. Unclear however, how this fix affects any further quests.
 * Random creatures such as mole rats, Old Lady Gibson, her dogs, and/or even a deathclaws may spawn outside the back door when leaving the main building. Sometimes all three spawn at once, and immediately attack you (the sight of all of them running toward you at once, growling, hissing and firing, is something to see). Shooting or attacking Old Lady Gibson's dogs when they spawn with result in the nearby NCR troops to turn hostile toward you. It is possible to go to the other end of the solar panel yard and having Old Layy Gibson's dogs to become friendly again. Reloading the autosave fixes it.
 * After enabling Archimedes I Defense System, if the player fast travels away before the sequence finishes, the NCR will not be killed and the infamy will not be gained.
 * Note that if the player returns to the area, the sequence will eventually complete and the infamy with the NCR will be raised. Also note that activating the Archimedes I system is optional; it doesn't do anything useful other than kill a bunch of NCR, so if the player doesn't want to kill NCR, the best solution is not to activate it in the first place. Archimedes II is separate, and can still be powered without harming the NCR.
 * Choosing to disarm the Archimedes defense system after activating it may not work; the sequence may play anyway.
 * Test firing Archimedes laser can cause the game to freeze.
 * If the player leaves the room after activating Python, but before he does the fixes to the generator, he will be deactivated when walking back inside again, and will not perform the fixes.
 * The Archimedes I sequence may not play out even though activated at the mainframe.
 * If you obtain the password for the second terminal without talking to Rivas and activate Archimedes II, Rivas will refuse to talk to you afterward and the quest cannot be completed. Alternately, kill Rivas and the quest will complete or fail but no XP or Loot will be given to the Courier.
 * The XP reward for restoring power is given when the ps3 trophy is awarded and as such will only be given ONCE - be wary of this if you plan to activate the Archimedes I Defense System just to see the ensuing massacre.
 * Sometimes when connecting the terminals WITHOUT killing the guard dogs no computer screen will appear and for all your save files when: Aiming down scopes and Picking locks a blank computer screen will appear.
 * Three NCR guard dogs are guarding the east solar panel Mainframe. Despite being in good standing with NCR these dogs will attack you or any NCR that they see. Killing them within sight of any NCR soldier will make all NCR in the area hostile. To fix this bug you can kill the dogs with no NCR patrols nearby, or lure the dogs out of their cage and close to an NCR soldier who will see the dogs as a threat and dispose of them for you. You do not kill them and therefore get no infamy gain with the NCR. Alternatively, you can get in the cage, reset the mainframe connection and get out fast enough to lock them in again.
 * If you fast travel away before the sequence after using the switch on the tower finishes, the end quest dialogue with Ignacio is missing from the speech options. You can still finish the quest by killing him.
 * Sometimes when you go to select your choice of how to distribute power at the mainframe, and you have Gannon in your party, his speech options will not come through.  Thus never being able to retrieve the trust points needed to obtain Gannon's quest.

Behind the scenes

 * The title of this quest is a reference to a 1949 song, "That Lucky Old Sun", by Beasley Smith and Haven Gillespie.
 * The passwords to the Eastern and Western Reflector Control Terminals can be converted from hexadecimal into ASCII, producing the phrases "My voice is my passport." and "Too many secrets". The phrases are originally from the movie Sneakers (1992), starring Robert Redford. They were used as computer passwords in that movie.


 * A number of remaining resources indicate that this quest at one point included a method for completing it on behalf of the Brotherhood of Steel, allowing them to take over the facility. Among other resources, the quest includes greeting dialogue for Brotherhood guards, indicating their satisfaction at gaining control of HELIOS One. Other unused resources include the guards themselves (FormID ) as well as the corresponding dialogue faction for these guards.

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