In Fallout 2, after you beat the game, you can continue playing. Remember that defunct vault near the beginning? The one with the toxic sludge on the ground and the elevator where you can kill golden geckos? It's called "Toxic Caves" on the world map, but it's clearly a very small vault with three levels, including the first cave level where you take a ladder down to the actual vault structure.
If you have one of the original pressings of the game and haven't patched it, you can return to the Toxic Caves after the game is over. If you have the item "Heart Pills" from the Westin murder case, you can kill yourself in the elevator
After the usual death scene plays, the screen will stay black without the menu opening back up. After several minutes, you will begin to hear a hollow, echoing white noise cave-type sound. The screen will slowly fade back in and your character will be in a pile of that nasty biomass goo that was around the Master in the first game. Your character will stand up and the usual ambient soundtrack will start playing, but the white noise continues.
Explore this new level but DO NOT pick any locks. Those areas are extremely off limits and the developers put some very nasty programming tricks into the code to protect their secrets.
As you continue further into the level, the white noise will increase in volume and the ambient soundtrack will begin to glitch out. This may be because the Fallout engine wasn't designed to be able to play two music tracks simultaneously.
Passing locked door after locked door, you will come upon many of the characters you met earlier in the game. Oddly, only characters that died or that would reasonably be expected to die after you last saw them are the only ones you will find. Like the official endings, the characters found vary depending on how you played the game.
If you were the good guy and tried to solve problems without violence, you will find only a few bad guys and other unfortunate victims here. If you slaughtered every down, however, you will see several-hundred characters.
Regardless of what you did earlier, none of the characters will speak to you or react in any way. They can't be pick-pocketed, killed, pushed aside, or healed. If you even try to use First Aid, Doctor, or any healing items on them, a text box pops up that says, "It's much too late for that, Chosen."
It would appear that this place is Purgatory or, possibly, Hell (based on the fact that it's populated entirely by dead characters). The final character, who stands just before the final door, is always the player character model from the first game. This is the only character you can interact with and, as you approach, the white noise reaches a crescendo and the ambient music abruptly cuts out.
If you simply bypass him/her and open the final door, the game will play the end credits once again, but with pictures of Hiroshima and Nagasake victims in the background. This is in extremely poor taste and many have wondered why the creators would be so insensitive. When asked, they deny the sequence exists and call it a hack that was never in the official game at all.
After the end credits are over, you are greeted with a typical game over screen and get booted to the desktop.
If you talk to the final character, he will explain that he is, in fact, the Vault Dweller from the first game - your ancestor. He will tell you that he is disappointed in the way you turned out. He turns his back on you and your character collapses in a pile of bones, a death animation that I have never seen in any other part of the game. Afterward, the game fades to white and the computer locks up, forcing a hard reset.
There is a third option: those locked doors I mentioned earlier. There is one door; it's always random which door it is, but if you get lucky you can use any heavy explosive to blow it open. Inside, you will find a single foot locker containing a 10mm pistol with no clip in the picture and no ammo. None of your normal 10mm ammo can be used with it.
You can 'load' the gun with the 'Easter Egg' found in the basement of New Reno Arms, however. Fire this at the final character and the game will cut to an over-the-shoulder video showing a young man playing an unidentified game similar to Fallout.
Some people claim this is an early version of either Fallout Tactics or Van Buren, but nothing on the screen seems to fit the descriptions of either games. In addition, neither game had started development at the time of the original release of Fallout 2.
The video itself is poorly lit, with the apparent intention of being a creepy cipher, but nothing spooky actually happens in the video. The man simply plays the unknown game and the video slowly fades back to your desktop. It's a cool trick, but I'm not sure how they managed a gradually translucing screen back then.
Another strange trick is that according to many players, the final character always matches the character they used in Fallout 1. Both gender and apparel at the end of the previous game are represented. At first, this would appear to be a save game hack not unlike Psycho Mantis in Metal Gear Solid, but the trick works even if the first game was played on a different computer without any of the data transferred to the new PC.
It's recommended that you do not turn on any televisions in your house for several hours after experiencing this third ending. You will quickly realize that the white noise in the game is coming from your television. Cable, satellite, and even antenna (if you still have that) are all somehow incapable of picking up a signal for some time after the third ending.
Computers and internet connections, however, still seem to work. That's how I'm writing this to you now. The funny thing, however, is that I turned my television off nearly an hour ago, as well as my computer speakers, but I still hear the static getting louder.