Revenge Of the Sith (Spoilers)

[MJD]

Originally Posted by Savior Why the fuck would a robot cough?

Grievious was a warlord alien that was pretty much killed and was turned into an Android to keep him alive, much like Anakin who is also an android. He had a confrontation with Mace Windu that you would see in the later chapters of the Clone Wars micro-series that rendered him pretty fucked up, hence the coughing.

Grievious hates the fact that he is part droid and hates being called a droid cos if anything he is an android.