shells hsells sehlls eshlls heslls ehslls shlels hslels slhels lshels hlsels lhsels selhls eslhls slehls lsehls elshls leshls helsls ehlsls hlesls lhesls elhsls lehsls shells hsells sehlls eshlls heslls ehslls shlels hslels slhels lshels hlsels lhsels selhls eslhls slehls lsehls elshls leshls helsls ehlsls hlesls lhesls elhsls lehsls shlles hslles slhles lshles hlsles lhsles shlles hslles slhles lshles hlsles lhsles sllhes lslhes sllhes lslhes llshes llshes hllses lhlses hllses lhlses llhses llhses sellhs esllhs slelhs lselhs elslhs leslhs sellhs esllhs slelhs lselhs elslhs leslhs sllehs lslehs sllehs lslehs llsehs llsehs ellshs lelshs ellshs lelshs lleshs lleshs hellss ehllss hlelss lhelss elhlss lehlss hellss ehllss hlelss lhelss elhlss lehlss hlless lhless hlless lhless llhess llhess ellhss lelhss ellhss lelhss llehss llehss shelsl hselsl sehlsl eshlsl heslsl ehslsl shlesl hslesl slhesl lshesl hlsesl lhsesl selhsl eslhsl slehsl lsehsl elshsl leshsl helssl ehlssl hlessl lhessl elhssl lehssl shesll hsesll sehsll eshsll hessll ehssll shsell hssell sshell sshell hssell shsell seshll esshll ssehll ssehll esshll seshll hessll ehssll hsesll shesll eshsll sehsll shlsel hslsel slhsel lshsel hlssel lhssel shslel hsslel sshlel sshlel hsslel shslel slshel lsshel sslhel sslhel lsshel slshel hlssel lhssel hslsel shlsel lshsel slhsel selshl eslshl sleshl lseshl elsshl lesshl seslhl esslhl sselhl sselhl esslhl seslhl slsehl lssehl sslehl sslehl lssehl slsehl elsshl lesshl eslshl selshl lseshl sleshl helssl ehlssl hlessl lhessl elhssl lehssl heslsl ehslsl hselsl shelsl eshlsl sehlsl hlsesl lhsesl hslesl shlesl lshesl slhesl elshsl leshsl eslhsl selhsl lsehsl slehsl shelsl hselsl sehlsl eshlsl heslsl ehslsl shlesl hslesl slhesl lshesl hlsesl lhsesl selhsl eslhsl slehsl lsehsl elshsl leshsl helssl ehlssl hlessl lhessl elhssl lehssl shesll hsesll sehsll eshsll hessll ehssll shsell hssell sshell sshell hssell shsell seshll esshll ssehll ssehll esshll seshll hessll ehssll hsesll shesll eshsll sehsll shlsel hslsel slhsel lshsel hlssel lhssel shslel hsslel sshlel sshlel hsslel shslel slshel lsshel sslhel sslhel lsshel slshel hlssel lhssel hslsel shlsel lshsel slhsel selshl eslshl sleshl lseshl elsshl lesshl seslhl esslhl sselhl sselhl esslhl seslhl slsehl lssehl sslehl sslehl lssehl slsehl elsshl lesshl eslshl selshl lseshl sleshl helssl ehlssl hlessl lhessl elhssl lehssl heslsl ehslsl hselsl shelsl eshlsl sehlsl hlsesl lhsesl hslesl shlesl lshesl slhesl elshsl leshsl eslhsl selhsl lsehsl slehsl shllse hsllse slhlse lshlse hlslse lhslse shllse hsllse slhlse lshlse hlslse lhslse sllhse lslhse sllhse lslhse llshse llshse hllsse lhlsse hllsse lhlsse llhsse llhsse shlsle hslsle slhsle lshsle hlssle lhssle shslle hsslle sshlle sshlle hsslle shslle slshle lsshle sslhle sslhle lsshle slshle hlssle lhssle hslsle shlsle lshsle slhsle shlsle hslsle slhsle lshsle hlssle lhssle shslle hsslle sshlle sshlle hsslle shslle slshle lsshle sslhle sslhle lsshle slshle hlssle lhssle hslsle shlsle lshsle slhsle sllshe lslshe sllshe lslshe llsshe llsshe slslhe lsslhe ssllhe ssllhe lsslhe slslhe slslhe lsslhe ssllhe ssllhe lsslhe slslhe llsshe llsshe lslshe sllshe lslshe sllshe hllsse lhlsse hllsse lhlsse llhsse llhsse hlslse lhslse hsllse shllse lshlse slhlse hlslse lhslse hsllse shllse lshlse slhlse llshse llshse lslhse sllhse lslhse sllhse sellsh esllsh slelsh lselsh elslsh leslsh sellsh esllsh slelsh lselsh elslsh leslsh sllesh lslesh sllesh lslesh llsesh llsesh ellssh lelssh ellssh lelssh llessh llessh selslh eslslh sleslh lseslh elsslh lesslh sesllh essllh ssellh ssellh essllh sesllh slselh lsselh sslelh sslelh lsselh slselh elsslh lesslh eslslh selslh lseslh sleslh selslh eslslh sleslh lseslh elsslh lesslh sesllh essllh ssellh ssellh essllh sesllh slselh lsselh sslelh sslelh lsselh slselh elsslh lesslh eslslh selslh lseslh sleslh sllseh lslseh sllseh lslseh llsseh llsseh slsleh lssleh sslleh sslleh lssleh slsleh slsleh lssleh sslleh sslleh lssleh slsleh llsseh llsseh lslseh sllseh lslseh sllseh ellssh lelssh ellssh lelssh llessh llessh elslsh leslsh esllsh sellsh lselsh slelsh elslsh leslsh esllsh sellsh lselsh slelsh llsesh llsesh lslesh sllesh lslesh sllesh hellss ehllss hlelss lhelss elhlss lehlss hellss ehllss hlelss lhelss elhlss lehlss hlless lhless hlless lhless llhess llhess ellhss lelhss ellhss lelhss llehss llehss helsls ehlsls hlesls lhesls elhsls lehsls heslls ehslls hsells shells eshlls sehlls hlsels lhsels hslels shlels lshels slhels elshls leshls eslhls selhls lsehls slehls helsls ehlsls hlesls lhesls elhsls lehsls heslls ehslls hsells shells eshlls sehlls hlsels lhsels hslels shlels lshels slhels elshls leshls eslhls selhls lsehls slehls hllses lhlses hllses lhlses llhses llhses hlsles lhsles hslles shlles lshles slhles hlsles lhsles hslles shlles lshles slhles llshes llshes lslhes sllhes lslhes sllhes ellshs lelshs ellshs lelshs lleshs lleshs elslhs leslhs esllhs sellhs lselhs slelhs elslhs leslhs esllhs sellhs lselhs slelhs llsehs llsehs lslehs sllehs lslehs sllehs
Note: these 'words' (valid or invalid) are all the permutations of the word shells. These words are obtained by scrambling the letters in shells.