scrud csrud srcud rscud crsud rcsud scurd csurd sucrd uscrd cusrd ucsrd srucd rsucd surcd usrcd ruscd urscd crusd rcusd cursd ucrsd rucsd urcsd scrdu csrdu srcdu rscdu crsdu rcsdu scdru csdru sdcru dscru cdsru dcsru srdcu rsdcu sdrcu dsrcu rdscu drscu crdsu rcdsu cdrsu dcrsu rdcsu drcsu scudr csudr sucdr uscdr cusdr ucsdr scdur csdur sdcur dscur cdsur dcsur sudcr usdcr sducr dsucr udscr duscr cudsr ucdsr cdusr dcusr udcsr ducsr srudc rsudc surdc usrdc rusdc ursdc srduc rsduc sdruc dsruc rdsuc drsuc sudrc usdrc sdurc dsurc udsrc dusrc rudsc urdsc rdusc drusc udrsc dursc cruds rcuds curds ucrds rucds urcds crdus rcdus cdrus dcrus rdcus drcus cudrs ucdrs cdurs dcurs udcrs ducrs rudcs urdcs rducs drucs udrcs durcs
Note: these 'words' (valid or invalid) are all the permutations of the word scrud. These words are obtained by scrambling the letters in scrud.