I’m not really sure of any other ‘masters’ as I don’t think we’ve met any? Well not since 2005, only the one I presume! So anyway, if there is more than 1 master… my favorite is the ‘Master’ who plays the ‘master’ in Utopia, The Sound of Drums and The Last of The Time Lords. You get which Master I’m on about?
Anyhow, what a guy… literally. He’s clever in every way, although defeatable yes, but ever so clever. Marvelous in a way. I mean what other villain can indoctrinate the great British isle’s in elected him prime minster… manifest himself into their memories and gain their trust, host an alien invasion and practically take over the world? Well the Master I suppose!