Hi, essay help needed, whoever's willing :)?

It's entitled "At the end of the play, Malcom describes Macbeth as a 'butcher'. do you think Macbeth is merely portrayed as a 'butcher'? (40 marks)".Now, I do English language and English Literature, and, lets face it, this is Shakespeare - so, it's immediately obvious to me that Macbeth is not portrayed as "merely" a butcher. My problem is, how on Earth can I string this answer out for long enough in order for it to constitute the whole 40 marks? Any ideas on what other areas I could address to pad it out etc? It's in for Wednesday, so quick answers would be appreciated. Thank you.