babka abbka bbaka bbaka abbka babka bakba abkba bkaba kbaba akbba kabba bbkaa bbkaa bkbaa kbbaa bkbaa kbbaa abkba bakba akbba kabba bkaba kbaba babak abbak bbaak bbaak abbak babak baabk ababk baabk ababk aabbk aabbk bbaak bbaak babak abbak babak abbak ababk baabk aabbk aabbk baabk ababk bakab abkab bkaab kbaab akbab kabab baakb abakb baakb abakb aabkb aabkb bkaab kbaab bakab abkab kabab akbab akabb kaabb aakbb aakbb kaabb akabb bbkaa bbkaa bkbaa kbbaa bkbaa kbbaa bbaka bbaka babka abbka babka abbka bkaba kbaba bakba abkba kabba akbba bkaba kbaba bakba abkba kabba akbba abkab bakab akbab kabab bkaab kbaab abakb baakb aabkb aabkb baakb abakb akabb kaabb aakbb aakbb kaabb akabb bkaab kbaab bakab abkab kabab akbab
Note: these 'words' (valid or invalid) are all the permutations of the word babka. These words are obtained by scrambling the letters in babka.