rider irder rdier drier idrer direr riedr iredr reidr eridr ierdr eirdr rdeir dreir redir erdir derir edrir iderr dierr iedrr eidrr deirr edirr ridre irdre rdire drire idrre dirre rirde irrde rride rride irrde rirde rdrie drrie rrdie rrdie drrie rdrie idrre dirre irdre ridre drire rdire rierd irerd reird erird ierrd eirrd rired irred rried rried irred rired rerid errid rreid rreid errid rerid ierrd eirrd irerd rierd erird reird rderi dreri redri erdri derri edrri rdrei drrei rrdei rrdei drrei rdrei rerdi errdi rredi rredi errdi rerdi derri edrri dreri rderi erdri redri iderr dierr iedrr eidrr deirr edirr idrer direr irder rider drier rdier ierdr eirdr iredr riedr eridr reidr derir edrir dreir rdeir erdir redir
Note: these 'words' (valid or invalid) are all the permutations of the word rider. These words are obtained by scrambling the letters in rider.