An interesting thing I found while messing around in Portal, what appears to be a cut line of dialogue that was removed very late in development.
The cut line appears in the Portal Beta, although at an earlier point in the escape, and, in this moment, a more threatening "Oh, I'm gonna kill you" is played. I guess they just kept moving that moment up through the escape until it landed where it did in the final game.
![](https://i.ytimg.com/vi/54KZgsOCpk4/maxresdefault.jpg)