Take it Back!

 is a Fallout 3 quest. It is also a Xbox 360/PC achievement and PlayStation 3 Trophy.

Summary
Take It Back! is the final main quest, with the game ending immediately after its completion. In this quest, the player and the Lyons' Pride assault the Jefferson Memorial in hopes of activating Project Purity. The colossal, crude, yet brutally effective robot Liberty Prime paves the way, annihilating numerous Vertibirds and Enclave soldiers, as well as the force fields erected by the Enclave.

Attack!
To begin the advance on the Jefferson Memorial, the player must speak with Sarah Lyons.

Note that once the order to attack has been given the green light, all functions and services in the Citadel will cease. All NPCs will spout encouraging phrases such as, "The Purifier is as good as ours!" if spoken to. If the player has anything to do in the Citadel, he or she must complete their task before commencing the attack.

Following the order to attack, the Brotherhood's massive Mini-Nuke-tossing, laser-armed robot Liberty Prime will be hoisted out of the Citadel on a crane and the Lyons' Pride will dutifully follow it, as should the player. Once outside the Citadel, the monstrous machine will begin stomping its way to the fallen bridge. There is a Raider hideout under the broken bridge, but they end up being killed very quickly by the Lyons' Pride. Liberty Prime will take down the photonic resonance barriers set up by the Enclave by walking into them.

Once on the bridge, the Enclave will desperately throw everything it has at the Brotherhood's machine: Soldiers, Vertibirds, and artillery. Unfortunately, Liberty Prime will not clean up all resistance, so the player must do some mopping up. Liberty Prime, thankfully, is a powerful anti-aircraft weapon, so the player doesn't need to waste time and munitions trying to down the incoming Vertibirds. The artillery shells tend to arc in from both sides of the bridge, but are notoriously inaccurate. Exploding vehicles are very deadly, so the player should find cover either behind Liberty Prime, or behind previously exploded vehicles. The player may feel intimidated by the concussive blasts, but will rarely take damage from them. The ground troops are the only threat to the player, as they are usually spaced out enough to avoid being wiped out all at once by the Mini-Nuke blasts. Targeting the ground troops can be a pain due to all the screen-shaking occurring (Mini-Nuke and artillery shell explosions) so V.A.T.S. is a good alternative to freehand aiming.

Liberty Prime cannot be stopped, and will inexorably clear a bloody path to the Memorial. The player and Lyons' Pride can come under attack from targets on a catwalk between buildings after clearing the bridge from the Citadel. It is possible to hustle to the near building, enter the door, run up several flights of stairs, and emerge beside the enemies on the catwalk, but this is a very impractical way of doing the job: a ranged weapon will work just fine. Melee and Unarmed characters can simply let the Lyons' Pride finish up these troops, but they take quite a while. Either way, Liberty Prime will continue carving his way though the resistance, past the Irradiated Metro and onwards to a second bridge. At the end is where Liberty Prime stops, and holds his position along with the rest of the Lyons' Pride while Sarah Lyons and the player dash inside the Jefferson Memorial through the Gift Shop.

There is light resistance inside the Gift Shop, usually three or four Enclave soldiers. The player as well as Lyons should be able to clear the room. Grenades work well in these quarters.

The Rotunda
After entering the Rotunda, the doors seal shut. Not locked, nor pickable, completely sealed. There is no leaving the Rotunda after entering it. Colonel Autumn is waiting for the player and Lyons in the Rotunda, and locks the player in dialogue. He seems unsurprised at the player's arrival at the purifier. The player has two choices at this point:


 * Talk Colonel Autumn out of attacking. This requires a high Speech skill. After conceding defeat, he will tell the player he will leave him or her to their fate. After this, Sarah Lyons will give a short remark on the player's decision, depending on his or her Karma.


 * Fight Colonel Autumn. The Colonel isn't terribly hard to defeat, but his bodyguards are tougher.

After resolving the situation and heading up the stairs to the control room, a panicked Dr. Li will key the intercom: Project Purity has sustained severe damage, and will soon self-destruct!

Now, the game has the player make one final decision:

Decision 1: Self-sacrifice or sacrifice another.
Damage to Project Purity has resulted in an incredible radiation buildup that will overwhelm anyone who is in the chamber during activation regardless of whatever preventative measures they have taken (e.g. Rad Away, Rad-X, or Radiation Resistance).

If the player hasn't figured it out from James' notes and recordings, the purifier password is 2-1-6 (referring to the verse from Revelation which Catherine loved). If the player follows James to the Purifier when he first enters the Memorial in The Waters of Life, James points out the code and repeats the passage. The player is supposed to infer it from James' dialogue about the Lone Wanderer's mother, and the picture hiding his safe in the Vault 101 clinic. This can be verified by forcing Sentinel Lyons to start the Purifier (your character tells her the passcode in dialog).

Choices
There are only two choices of who activates Project Purity: the player character or Sentinel Lyons. If players ask their companions to assist, they will refuse even if they are immune to radiation and bound to the player's command, such as Sergeant RL-3 or Charon. Activating the console will be fatal to the person inside the chamber, as it was to James. The medicine that saved Colonel Autumn from the same fate cannot be obtained during the game.

Companion Responses

 * Fawkes

Fawkes, one of the companions the player may take with them, has great radiation resistance (or possibly immunity) as a result of being a super-mutant. However, like any other companion character, his dialog option has him refuse to enter the chamber, mysteriously claiming it is the player character's "destiny."

Whether this is because Fawkes believed himself unable to survive, if he had other reasons for declining the player (such as feeling that the debt had been repaid, or if he genuinely believes in destiny) is not explained. Regardless, Fawkes turns out to be a red herring: the player is forced into a decision to either sacrifice themselves or make a true hero (Sentinel Lyons) make the sacrifice for them.

Fawkes may, however, follow the player into the chamber.


 * Dogmeat

In addition, a new dialog option with Dogmeat opens up, wherein the Lone Wanderer can say some final words to his or her canine companion, stating: "I think it's time for us to say goodbye, old buddy. Take care of yourself, okay?" Dogmeat in response whines. As intelligent as the canine may be, there is no option to have Dogmeat activate Project Purity.


 * Sergeant RL-3

Even if you took Sergeant RL-3 (Mister Gutsy combat droid, which is immune to radiation) into the rotunda with you and command it to go in to turn on the purifier he "declines" and says:

There is no Robotics Expert dialogue option in the conversation.


 * Charon

Ghouls are immune to (and healed by) radiation, so Charon presumably could survive the radiation like Fawkes, but he refuses. Perhaps the intense radiation would turn him feral. Another reason for him to not go in, as stated when asked to retrieve the G.E.C.K. is that his contract only requires him to help with combat. Charon simply says:


 * Butch

Butch, understandably, will refuse out of fear of dying and of becoming a ghoul, stating:


 * Star Paladin Cross

She respectfully refuses of course:


 * Clover

Apparently, there are limits to Clover's mental conditioning and slave collar. She refuses as well:


 * Jericho

Jericho also refuses, stating simply:

Decision 2: Project Impurity.
If the player still has in their possession the Modified FEV created by President Eden, they can insert it into the water filter. As in Fallout 2, by design the only creatures spared by the Modified FEV are pure strain humans who are still within vaults or the Enclave and possibly the Brotherhood of Steel. This would reverse a great deal of genetic damage done by the nuclear apocalypse, but at the cost of complete eradication of nearly all life on the wasteland.

This decision is actually listed in the player's Pip-Boy as a separate quest called Project Impurity; however, it cannot be completed if the player turned in the Modified FEV to Owyn Lyons before departing the Citadel.

Decision 3: Do nothing.
If the player chooses to, they may simply not go into the purifier. This results in Project Purity quickly exploding, along with any chance of pure water for the entire wasteland or to introduce the Modified FEV into the water supply. An ending sequence will still be played, and it will count as an ending. The last thing the player will see is the destruction of the purifier. Just like all other endings, this does not result in free-play either.

Game Over
There is currently no way to continue playing the game after completing this quest, short of a hack or modification. Whether the player chooses to go in there themselves or make Sentinel Lyons do it, the game ends. The ending cinematic plays and the player is returned to the main menu. However, saving before starting the quest, then finishing it and reloading, can be used to acquire a achievement/trophy and yet continue playing the game.

However, Jeff Gardiner has claimed that neither ending is canon in the May 5th 2009 "Broken Steel" downloadable epilogue, citing a need to let the game continue without being hampered by the original endings. However, the decision you make with the purifier will still be important, as the choice you make will dramatically change the gameplay.

Modifications/hacks
For PC users, one mod exists to play after the ending sequence, regardless of the choice made (if the player chooses to activate the purifier himself, the airlock doors will remain open, allowing him/her to run out as soon as the purifier starts. On top of this the player "death sequence animation" won't play.). It is found here. Because this is unofficial however, none of the above changes happen after the game, though there is an included module for a purified Potomac.

Bugs

 * When Liberty Prime is crossing the Potomac bridge, depending on the bombardment, it is possible for Liberty Prime to get stuck on the bridge after being hit by a blast. Liberty Prime may also get stuck by the Enclave's dropships on the bridge. Firing a few Mini Nukes with the Fat Man on the dropships will clear the road and Liberty Prime resumes its path.
 * It might be debatable whether this is a bug or intentional or just "dumb AI" but all of the Lyon's Pride but Sarah often get stuck in the bombardment on the bridge and die or get unconscious. -- This can be prevented by standing behind the Pride members as they move into formation on the bridge and gently shoving them forward out of harms way. This is easiest to do in 3rd person mode.
 * Also Liberty Prime might also appear to be floating in the air while on the bridge, you can fix this by killing enclave troops around liberty prime.
 * Sometimes, Liberty Prime will stop attacking Enclave forces after reaching the Jefferson Memorial. He will simply attack a few soldiers on the scaffolding and then walk back to the end of the bridge and stand, leaving a great deal of the soldiers for you.
 * Also if you kill anyone in the Citadel after accepting "Take It Back!" everyone will seem like they haven't noticed but the soldiers will not move when Lyons tells everyone to move out, and Liberty Prime will remain stuck at the opening gate, or turn hostile toward you and kill you. So load off an autosave, before you continue to be stuck in this glitch, unable to end the game. Also sometimes Elder Lyons or Sentinel Lyons will chase you down, if you fast traveled and become hostile toward you. I haven't found anyway to fix this glitch other then Loading a save/auto-save.
 * Right after leaving the Citadel, Liberty Prime may just cross the Potomac on an invisible bridge. All of the Lyons Pride members will be able to cross the bridge (as will you since you are considered a member of Lyons Pride at this point). This has no effect on the actual gameplay, but it is very unrealistic.
 * Some characters may get stuck up on misc. objects.
 * At one point, all members of the Lyons Pride kept shooting at an Enclave corpse (as did Charon) and the player was unable to interact with the body. Charon will simply stop and follow the player once again if the player walks too far away, but I haven't found a way to get the Lyons Pride to continue.
 * After leaving the Citadel, Liberty Prime may just stop moving altogether. If this happens, reload an earlier save and he should start to move.
 * Sometimes randomly in the battle, all the soldiers will return to the citadel (most of the time when one of them die in battle) and Liberty prime will disappear.
 * You can attack Liberty Prime and your cursor will turn red. If you (and Fawkes if you have him) attack him from behind, sometimes cars will appear and react as if they have been blown up. If you walk up the platform and attack him face to face, he'll attack you ONCE and you will die. The game may set your autosave point to the time when the cars parts spawned and landed.
 * When you are in the courtyard of the citadel and began to move out to began your attack the screen will instantly freeze, If you fast travel and go back to the citadel Liberty Prime will not move and stay still meaning there is no end to the game.
 * It's possible for the game to randomly freeze during initial invasion, it could be caused by moving too far away from the Pride.

Future Expansions
Main article: Fallout 3 downloadable content

Ending Movies
The ending movie varies depending on how the player plays the game, and some of the largest differences are seen depending on what the player has done during Take it Back! See Fallout 3 endings for more info.

Trivia

 * Liberty Prime may be a pun on Optimus Prime from the Transformers series. One of his quotes, "Freedom is the right of every sovereign American!", plays off Prime's famous "Freedom is the right of all sentient beings," as well.


 * Liberty Prime in Take it Back! is an example of the plot device known as Chekhov's gun, because it is introduced as a background element early on in the story, but its purpose and reason for existence are not revealed until needed.