fenks efnks fneks nfeks enfks nefks fekns efkns fkens kfens ekfns kefns fnkes nfkes fknes kfnes nkfes knfes enkfs nekfs eknfs kenfs nkefs knefs fensk efnsk fnesk nfesk enfsk nefsk fesnk efsnk fsenk sfenk esfnk sefnk fnsek nfsek fsnek sfnek nsfek snfek ensfk nesfk esnfk senfk nsefk snefk feksn efksn fkesn kfesn ekfsn kefsn feskn efskn fsekn sfekn esfkn sefkn fksen kfsen fsken sfken ksfen skfen eksfn kesfn eskfn sekfn ksefn skefn fnkse nfkse fknse kfnse nkfse knfse fnske nfske fsnke sfnke nsfke snfke fksne kfsne fskne sfkne ksfne skfne nksfe knsfe nskfe snkfe ksnfe sknfe enksf neksf eknsf kensf nkesf knesf enskf neskf esnkf senkf nsekf snekf eksnf kesnf esknf seknf ksenf skenf nksef knsef nskef snkef ksnef sknef
Note: these 'words' (valid or invalid) are all the permutations of the word fenks. These words are obtained by scrambling the letters in fenks.