How To: Earn the "Kill Bill" and "Supreme Sacrifice" achievements in L4D 1&2 Xbox 360

At the very end of Left 4 Dead 2's new DLC "The Sacrifice" there are two achievements that you can receive in the game, Kill Bill and Supreme Sacrifice. Although it's easy to get Supreme Sacrifice, in order to get both at the same time you have to play as Bill when you go to turn on the generator. Not quite getting it? Check out this video for a quick tutorial on how to get both of the achievements!