crass rcass carss acrss racss arcss crsas rcsas csras scras rscas srcas casrs acsrs csars scars ascrs sacrs rascs arscs rsacs sracs asrcs sarcs crass rcass carss acrss racss arcss crsas rcsas csras scras rscas srcas casrs acsrs csars scars ascrs sacrs rascs arscs rsacs sracs asrcs sarcs crssa rcssa csrsa scrsa rscsa srcsa crssa rcssa csrsa scrsa rscsa srcsa cssra scsra cssra scsra sscra sscra rssca srsca rssca srsca ssrca ssrca cassr acssr csasr scasr ascsr sacsr cassr acssr csasr scasr ascsr sacsr cssar scsar cssar scsar sscar sscar asscr sascr asscr sascr ssacr ssacr rassc arssc rsasc srasc asrsc sarsc rassc arssc rsasc srasc asrsc sarsc rssac srsac rssac srsac ssrac ssrac assrc sasrc assrc sasrc ssarc ssarc
Note: these 'words' (valid or invalid) are all the permutations of the word crass. These words are obtained by scrambling the letters in crass.