nacst ancst ncast cnast acnst canst nasct ansct nsact snact asnct sanct ncsat cnsat nscat sncat csnat scnat acsnt casnt ascnt sacnt csant scant nacts ancts ncats cnats acnts cants natcs antcs ntacs tnacs atncs tancs nctas cntas ntcas tncas ctnas tcnas actns catns atcns tacns ctans tcans nastc anstc nsatc snatc asntc santc natsc antsc ntasc tnasc atnsc tansc nstac sntac ntsac tnsac stnac tsnac astnc satnc atsnc tasnc stanc tsanc ncsta cnsta nscta sncta csnta scnta nctsa cntsa ntcsa tncsa ctnsa tcnsa nstca sntca ntsca tnsca stnca tsnca cstna sctna ctsna tcsna stcna tscna acstn castn asctn sactn csatn scatn actsn catsn atcsn tacsn ctasn tcasn astcn satcn atscn tascn stacn tsacn cstan sctan ctsan tcsan stcan tscan
Note: these 'words' (valid or invalid) are all the permutations of the word nacst. These words are obtained by scrambling the letters in nacst.