guff ugff gfuf fguf ufgf fugf guff ugff gfuf fguf ufgf fugf gffu fgfu gffu fgfu ffgu ffgu uffg fufg uffg fufg ffug ffug
Note: these 'words' (valid or invalid) are all the permutations of the word guff. These words are obtained by scrambling the letters in guff.