Famous Movie Lines That Were Actually Improvised
Aliens
You either love or hate Bill Paxton’s alternately tough guy/whiny baby performance in Aliens, but the fact is that Paxton’s Private Hudson doesn’t really say a lot of lines that were actually in the script.
In particular, many of Paxton’s reactions, such as the famous “Game over, man! Game over” were not in the script at all, and they were done off the top of Bill’s head.

Aliens
Do with that information what you will.