Yoda (Frank Oz)
Character Analysis
Ah, Yoda. Our wise, grammatically confused little green friend. Much of his character development occurs in some of the other Star Wars movies, so in Revenge of the Sith, he mostly serves as a mentor figure for Anakin and Obi-Wan Kenobi.
He's kind of like a Jedi moral compass, helping to pass judgment on difficult decisions, sensing disturbances in the Force, and even serving as a dream analyst when Anakin is truly distressed.
Also, because these movies take place roughly 30 years before the original trilogy does, he's young and spry enough to be a major threat with a lightsaber, contributing to one of the cooler fight scenes in the movie against Emperor Palpatine.
As one of the senior Jedi Masters on the Council, Yoda is a wise leader and compassionate mentor. Unfortunately, though, that's not enough to keep Anakin in line. Tied him up, he should have. 20/20 is hindsight.