Tie between the three originals. TFA and RO were both great, but not on that level. TPM was watchable, but that's about where my praise ends. AotC and RotS were garbage and were, without exaggeration, two of the worst movies I've ever had to sit through.
Kill 1 man: You are a murderer. Kill 10 men: You are a monster.
Kill 100 men: You are a hero. Kill 10,000 men, you are a conqueror!