Man they are both SO good, its really hard to pick one. Great arguments for both.  Vader is just so menacing. Like that scene puts him above most horror icons like Jason and Freddy for me because of how powerless a room full of armed soldiers were against him and how efficiently and brutally he cuts through them. Lukes is a more impressive feat because hes effortlessly taking down a hallway full of droids that are normally very difficult to kill. The mandalorian is a badass and nearly died just taking on a single droid. Of course, I have no doubt Vader would have just as easily handled the phase III dark troopers.