2. Obi-Wan Kenobi (Star Wars)
With the final words "if you strike me down..." it was pretty obvious to everyone that Obi-Wan Kenobi's sacrificial death was a necessary component of the Star Wars saga. Driving Luke Skywalker forward both emotionally and spiritually, Obi-Wan's demise is the catalyst for the rebel forces. Frankly, Vader should've been smart enough to realize that stuff was gonna go down after that battle and just let the old Jedi master go in peace. Instead he cuts him down with a light saber, spawning another five films and an entire movie universe.