Fallout 3 (Walkthrough) with DLC's -> Fallout 3: Broken Steel
After activating the add-on, leveling your character to level 30 and unlocking new perks will become available. Also, don't forget about the karma achievements at level 30 :)
We're completing the final quest of Fallout 3. Regardless of how you activated the purifier (yourself or sent Sarah), you'll wake up in one of the rooms of the Brotherhood of Steel Citadel. Elder Lyons stands before you; speak with him. It turns out there was a powerful energy surge, which saved you and Sarah. The purifier is working, but we need to defeat the remaining Enclave forces. Next, speak with Scribe Rothschild and receive instructions. Then, head to the Rockland road tunnel to meet with Paladin Tristan. After a pleasant conversation, accompany the squad during the assault. The robot broke down, too bad! Well, never mind, let's go inside the building. Be careful, there are too many Enclave soldiers. Climb the stairs, go through the door and down the corridor, then down the stairs, dealing with the enemies. Go straight ahead and right down the corridor. Then up the stairs, go through two doors, and that's it, we're at the satellite control terminal. Download the data to the external device and go to Scribe Rothschild at the Citadel. Next, go to Elder Lyons for the achievement.
Go see Tristan. He'll send you to the Olney Refinery to find a Tesla Coil to develop a new weapon. But Old Olney is a dangerous place, and if you talk to Scribe Valincourt, you can get a Deathclaw control device—that'll make your life a little easier. Enter the Olney Sewers. Be careful, there are plenty of Deathclaws here, and they're some of the most ferocious enemies in the Capital Wasteland. Then go up the stairs and talk to the ghouls. Then follow the marker down the corridor. We think we've made it, but then we hear the sound of a helicopter. Damn it, the Enclave soldiers are already here! Well, you know what to do with them, but Enclave special forces are serious business. Get to the automation control terminal and activate it, otherwise you'll die from radiation in the corridor! We see some kind of electrical thing, apparently that's how plasma weapons are made, so we head to the door. We activate the emergency switch and see even more shader madness – that's the Tesla Coil. Grab it and run to Tristan for the achievement, it's simple!
We get a new mission, which requires you to destroy the enemy stronghold at Adams Air Force Station. We head to White House Square and then go down the service hatch. I won't mention the super mutants, since after the Deathclaws, they're just cute. Turn right and we're in the Presidential Metro. Follow the marker and reach the S.P.S.T.M. identification terminal. Choose one of the options (science or eloquence) and gain access. Then go through the door behind the terminal. Crazy ghoul ripper-like creatures – that's something new. Get to the subway cars and activate the power panel if necessary. Then get into the first car and activate the subway controls. We're moving, hurray! We've arrived, head up the stairs and turn left, kill the Enclave soldiers, head straight to the door, and we're at Adams Air Force Base.
Turn left immediately. There's a crate of ammunition there, most importantly for the outpost orders and the Tesla Gun. It's a good weapon, by the way; it was worth the trouble we had in Old Olney. Okay, let's move forward, destroying turrets and Enclave soldiers along the way. This might not surprise you, but there are a lot of Enclave soldiers here, so be careful. Enter the air control building and look for an access terminal for the Enclave mobile platform. Climb to the very top; the terminal is waiting there. Next, enter this very platform. The objective has updated; now this platform needs to be destroyed with an orbital strike. First, disable the force field (using the terminal). You can get some information from Stiggs. Head to the stairs and then follow the marker. Disable the force fields using the terminals.
There's a decent supply of ammunition in the basement; you might need it. Once you reach the top of the platform, be prepared for a massive fight with soldiers, robots, and turrets. Next, head to the satellite control room door and activate the appropriate terminal option (among the destruction targets, you can see, for example, the Citadel, Rivet City, and others). We're interested in Adams Air Force Base. Climb to the top and speak with Sarah, who has just arrived. Enjoy the fireworks! Then, fly to the Citadel for gratitude and an achievement.
Source: geafox.net