a bin bag put over your head {cut the hole for your head of course} stick things like an old teabag , crunchie wrappers , potatoe pealings, yano the kinda thing, finish it with a piece of burnt toats on a string around your neck .
Or to really keep costs down, just wear a sash reading 'Mayor of Earth' across it and tell everyone that you're pinkiefriend in a parallel universe. Then insist everybody bows and kisses your hand.
I went for the cheap option last year by buying a cheap black/white witch wig and doing my own make-up. The entire outfit was out of my own wardrobe, including red fishnets tights...
A black cat - I once went to a Hallowe'en party as one, I had on a black top, black trousers, black high heel shoes and made myself a black tail (I think I plaited some black tights together or something), though I did buy one of those half face cat masks.
here,s a good one! last year my son went as half killed!(hauf kilt) scottish! wore a kilt and then wrapped the top half in bandages! some fake blood ! easy ! hope that helps!