Take it Back!

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

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.

The point of no return is right before entering the Jefferson Memorial rotunda. If you choose not to enter the rotunda, you may still exit Jefferson Memorial and map out. After you enter the rotunda, Lyons will comment of locking the area down and both doors out will be sealed (not locked, and as such unpickable via lockpicking and the console), preventing the player from leaving, although a companion fired at this time is still able to depart through these locked doors. Also note that, once you start the battle with Liberty Prime, all functions in The Citadel would cease. You can no longer shop there, or have any other real dialogue. All they say is "The Purifier is as good as ours!" This will also preclude you from recruiting Star Paladin Cross.

When the player and the remaining Lyons' Pride members finally reach the Project Purity control room, they discover Colonel Autumn and a few other Enclave troops waiting for them. Player characters with high Speech skill may convince Colonel Autumn to step aside. Others may (rather easily) dispatch the Colonel after a fruitless conversation.

At this point, the player is informed over the intercom that Project Purity has sustained damage, possibly deliberate or accidental, and is about to self-destruct. Contrary to the more open-ended nature of the rest of the game, the player is now forced into two decisions.

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 dialogue).

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 dialogue 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 dialogue option with Dogmeat opens up, wherein the lone wanderer can say some final words to his 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. Still, Charon simply says:


 * Butch

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


 * Star Paladin Cross

She 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 your Pip-Boy as a separate quest called Project Impurity; however, it cannot be completed if you turned over 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 April 2009 "Broken Steel" downloadable epilogue, citing a need to let the game continue without being hampered by the original endings.

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 (you will be 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 havn'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 and Liberty prime will disappear.

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
This is similar to the ending of "Star Trek II: The Wrath of Khan" when Spock enters a sealed chamber to restore power to the Enterprise and dies soon after due to radiation poisoning.

Liberty Prime may be a pun on Optimus Prime from the Transformers series.