How do you get emperor's guard in Lego star wars 3?

To unlock the Emperor's Guard in LEGO Star Wars III: The Clone Wars, you need to complete the mission titled "The Emperor's Guard," which is part of the game's story mode. Once you finish this mission, you can access the character from the character selection menu. Additionally, you can also unlock the Emperor's Guard by purchasing him using in-game studs after completing the necessary requirements.