11. Han Shoots First ('A New Hope')
This scene remains perhaps the most egregious example of George Lucas going back years later to revise his work and irreparably ruining it in the process. This famously (and controversially) tampered-with scene — in which Han blasts Greedo before the green-skinned bounty hunter has a chance to pull out his weapon — established Solo as a much more dangerous character than he ended up being. You can throw all the revisionist history out there you want, George. We all know who has the quicker draw.