ghasts hgasts gahsts aghsts hagsts ahgsts ghsats hgsats gshats sghats hsgats shgats gashts agshts gsahts sgahts asghts saghts hasgts ahsgts hsagts shagts ashgts sahgts ghatss hgatss gahtss aghtss hagtss ahgtss ghtass hgtass gthass tghass htgass thgass gathss agthss gtahss tgahss atghss taghss hatgss ahtgss htagss thagss athgss tahgss ghstas hgstas gshtas sghtas hsgtas shgtas ghtsas hgtsas gthsas tghsas htgsas thgsas gsthas sgthas gtshas tgshas stghas tsghas hstgas shtgas htsgas thsgas sthgas tshgas gasths agsths gsaths sgaths asgths sagths gatshs agtshs gtashs tgashs atgshs tagshs gstahs sgtahs gtsahs tgsahs stgahs tsgahs astghs satghs atsghs tasghs staghs tsaghs hastgs ahstgs hsatgs shatgs ashtgs sahtgs hatsgs ahtsgs htasgs thasgs athsgs tahsgs hstags shtags htsags thsags sthags tshags asthgs sathgs atshgs tashgs stahgs tsahgs ghasst hgasst gahsst aghsst hagsst ahgsst ghsast hgsast gshast sghast hsgast shgast gashst agshst gsahst sgahst asghst saghst hasgst ahsgst hsagst shagst ashgst sahgst ghasst hgasst gahsst aghsst hagsst ahgsst ghsast hgsast gshast sghast hsgast shgast gashst agshst gsahst sgahst asghst saghst hasgst ahsgst hsagst shagst ashgst sahgst ghssat hgssat gshsat sghsat hsgsat shgsat ghssat hgssat gshsat sghsat hsgsat shgsat gsshat sgshat gsshat sgshat ssghat ssghat hssgat shsgat hssgat shsgat sshgat sshgat gassht agssht gsasht sgasht asgsht sagsht gassht agssht gsasht sgasht asgsht sagsht gssaht sgsaht gssaht sgsaht ssgaht ssgaht assght sasght assght sasght ssaght ssaght hassgt ahssgt hsasgt shasgt ashsgt sahsgt hassgt ahssgt hsasgt shasgt ashsgt sahsgt hssagt shsagt hssagt shsagt sshagt sshagt asshgt sashgt asshgt sashgt ssahgt ssahgt ghatss hgatss gahtss aghtss hagtss ahgtss ghtass hgtass gthass tghass htgass thgass gathss agthss gtahss tgahss atghss taghss hatgss ahtgss htagss thagss athgss tahgss ghasts hgasts gahsts aghsts hagsts ahgsts ghsats hgsats gshats sghats hsgats shgats gashts agshts gsahts sgahts asghts saghts hasgts ahsgts hsagts shagts ashgts sahgts ghtsas hgtsas gthsas tghsas htgsas thgsas ghstas hgstas gshtas sghtas hsgtas shgtas gtshas tgshas gsthas sgthas tsghas stghas htsgas thsgas hstgas shtgas tshgas sthgas gatshs agtshs gtashs tgashs atgshs tagshs gasths agsths gsaths sgaths asgths sagths gtsahs tgsahs gstahs sgtahs tsgahs stgahs atsghs tasghs astghs satghs tsaghs staghs hatsgs ahtsgs htasgs thasgs athsgs tahsgs hastgs ahstgs hsatgs shatgs ashtgs sahtgs htsags thsags hstags shtags tshags sthags atshgs tashgs asthgs sathgs tsahgs stahgs ghstsa hgstsa gshtsa sghtsa hsgtsa shgtsa ghtssa hgtssa gthssa tghssa htgssa thgssa gsthsa sgthsa gtshsa tgshsa stghsa tsghsa hstgsa shtgsa htsgsa thsgsa sthgsa tshgsa ghssta hgssta gshsta sghsta hsgsta shgsta ghssta hgssta gshsta sghsta hsgsta shgsta gsshta sgshta gsshta sgshta ssghta ssghta hssgta shsgta hssgta shsgta sshgta sshgta ghtssa hgtssa gthssa tghssa htgssa thgssa ghstsa hgstsa gshtsa sghtsa hsgtsa shgtsa gtshsa tgshsa gsthsa sgthsa tsghsa stghsa htsgsa thsgsa hstgsa shtgsa tshgsa sthgsa gstsha sgtsha gtssha tgssha stgsha tsgsha gsstha sgstha gsstha sgstha ssgtha ssgtha gtssha tgssha gstsha sgtsha tsgsha stgsha stsgha tssgha sstgha sstgha tssgha stsgha hstsga shtsga htssga thssga sthsga tshsga hsstga shstga hsstga shstga sshtga sshtga htssga thssga hstsga shtsga tshsga sthsga stshga tsshga ssthga ssthga tsshga stshga gastsh agstsh gsatsh sgatsh asgtsh sagtsh gatssh agtssh gtassh tgassh atgssh tagssh gstash sgtash gtsash tgsash stgash tsgash astgsh satgsh atsgsh tasgsh stagsh tsagsh gassth agssth gsasth sgasth asgsth sagsth gassth agssth gsasth sgasth asgsth sagsth gssath sgsath gssath sgsath ssgath ssgath assgth sasgth assgth sasgth ssagth ssagth gatssh agtssh gtassh tgassh atgssh tagssh gastsh agstsh gsatsh sgatsh asgtsh sagtsh gtsash tgsash gstash sgtash tsgash stgash atsgsh tasgsh astgsh satgsh tsagsh stagsh gstsah sgtsah gtssah tgssah stgsah tsgsah gsstah sgstah gsstah sgstah ssgtah ssgtah gtssah tgssah gstsah sgtsah tsgsah stgsah stsgah tssgah sstgah sstgah tssgah stsgah astsgh satsgh atssgh tassgh stasgh tsasgh asstgh sastgh asstgh sastgh ssatgh ssatgh atssgh tassgh astsgh satsgh tsasgh stasgh stsagh tssagh sstagh sstagh tssagh stsagh hastsg ahstsg hsatsg shatsg ashtsg sahtsg hatssg ahtssg htassg thassg athssg tahssg hstasg shtasg htsasg thsasg sthasg tshasg asthsg sathsg atshsg tashsg stahsg tsahsg hasstg ahsstg hsastg shastg ashstg sahstg hasstg ahsstg hsastg shastg ashstg sahstg hssatg shsatg hssatg shsatg sshatg sshatg asshtg sashtg asshtg sashtg ssahtg ssahtg hatssg ahtssg htassg thassg athssg tahssg hastsg ahstsg hsatsg shatsg ashtsg sahtsg htsasg thsasg hstasg shtasg tshasg sthasg atshsg tashsg asthsg sathsg tsahsg stahsg hstsag shtsag htssag thssag sthsag tshsag hsstag shstag hsstag shstag sshtag sshtag htssag thssag hstsag shtsag tshsag sthsag stshag tsshag ssthag ssthag tsshag stshag astshg satshg atsshg tasshg stashg tsashg assthg sasthg assthg sasthg ssathg ssathg atsshg tasshg astshg satshg tsashg stashg stsahg tssahg sstahg sstahg tssahg stsahg
Note: these 'words' (valid or invalid) are all the permutations of the word ghasts. These words are obtained by scrambling the letters in ghasts.