faster afster fsater sfater asfter safter fatser aftser ftaser tfaser atfser tafser fstaer sftaer ftsaer tfsaer stfaer tsfaer astfer satfer atsfer tasfer stafer tsafer fasetr afsetr fsaetr sfaetr asfetr safetr faestr afestr feastr efastr aefstr eafstr fseatr sfeatr fesatr efsatr sefatr esfatr aseftr saeftr aesftr easftr seaftr esaftr fatesr aftesr ftaesr tfaesr atfesr tafesr faetsr afetsr featsr efatsr aeftsr eaftsr fteasr tfeasr fetasr eftasr tefasr etfasr atefsr taefsr aetfsr eatfsr teafsr etafsr fstear sftear ftsear tfsear stfear tsfear fsetar sfetar festar efstar seftar esftar ftesar tfesar fetsar eftsar tefsar etfsar stefar tsefar setfar estfar tesfar etsfar astefr satefr atsefr tasefr staefr tsaefr asetfr saetfr aestfr eastfr seatfr esatfr atesfr taesfr aetsfr eatsfr teasfr etasfr steafr tseafr setafr estafr tesafr etsafr fastre afstre fsatre sfatre asftre saftre fatsre aftsre ftasre tfasre atfsre tafsre fstare sftare ftsare tfsare stfare tsfare astfre satfre atsfre tasfre stafre tsafre fasrte afsrte fsarte sfarte asfrte safrte farste afrste fraste rfaste arfste rafste fsrate sfrate frsate rfsate srfate rsfate asrfte sarfte arsfte rasfte srafte rsafte fatrse aftrse ftarse tfarse atfrse tafrse fartse afrtse fratse rfatse arftse raftse ftrase tfrase frtase rftase trfase rtfase atrfse tarfse artfse ratfse trafse rtafse fstrae sftrae ftsrae tfsrae stfrae tsfrae fsrtae sfrtae frstae rfstae srftae rsftae ftrsae tfrsae frtsae rftsae trfsae rtfsae strfae tsrfae srtfae rstfae trsfae rtsfae astrfe satrfe atsrfe tasrfe starfe tsarfe asrtfe sartfe arstfe rastfe sratfe rsatfe atrsfe tarsfe artsfe ratsfe trasfe rtasfe strafe tsrafe srtafe rstafe trsafe rtsafe fasert afsert fsaert sfaert asfert safert faesrt afesrt feasrt efasrt aefsrt eafsrt fseart sfeart fesart efsart sefart esfart asefrt saefrt aesfrt easfrt seafrt esafrt fasret afsret fsaret sfaret asfret safret farset afrset fraset rfaset arfset rafset fsraet sfraet frsaet rfsaet srfaet rsfaet asrfet sarfet arsfet rasfet srafet rsafet faerst aferst fearst efarst aefrst eafrst farest afrest fraest rfaest arfest rafest ferast efrast freast rfeast erfast refast aerfst earfst arefst raefst erafst reafst fserat sferat fesrat efsrat sefrat esfrat fsreat sfreat frseat rfseat srfeat rsfeat fersat efrsat fresat rfesat erfsat refsat serfat esrfat srefat rsefat ersfat resfat aserft saerft aesrft easrft searft esarft asreft sareft arseft raseft sraeft rsaeft aersft earsft aresft raesft erasft reasft seraft esraft sreaft rseaft ersaft resaft faters afters ftaers tfaers atfers tafers faetrs afetrs featrs efatrs aeftrs eaftrs ftears tfears fetars eftars tefars etfars atefrs taefrs aetfrs eatfrs teafrs etafrs fatres aftres ftares tfares atfres tafres fartes afrtes frates rfates arftes raftes ftraes tfraes frtaes rftaes trfaes rtfaes atrfes tarfes artfes ratfes trafes rtafes faerts aferts fearts efarts aefrts eafrts farets afrets fraets rfaets arfets rafets ferats efrats freats rfeats erfats refats aerfts earfts arefts raefts erafts reafts fteras tferas fetras eftras tefras etfras ftreas tfreas frteas rfteas trfeas rtfeas fertas efrtas fretas rfetas erftas reftas terfas etrfas trefas rtefas ertfas retfas aterfs taerfs aetrfs eatrfs tearfs etarfs atrefs tarefs artefs ratefs traefs rtaefs aertfs eartfs aretfs raetfs eratfs reatfs terafs etrafs treafs rteafs ertafs retafs fstera sftera ftsera tfsera stfera tsfera fsetra sfetra festra efstra seftra esftra ftesra tfesra fetsra eftsra tefsra etfsra stefra tsefra setfra estfra tesfra etsfra fstrea sftrea ftsrea tfsrea stfrea tsfrea fsrtea sfrtea frstea rfstea srftea rsftea ftrsea tfrsea frtsea rftsea trfsea rtfsea strfea tsrfea srtfea rstfea trsfea rtsfea fserta sferta fesrta efsrta sefrta esfrta fsreta sfreta frseta rfseta srfeta rsfeta fersta efrsta fresta rfesta erfsta refsta serfta esrfta srefta rsefta ersfta resfta ftersa tfersa fetrsa eftrsa tefrsa etfrsa ftresa tfresa frtesa rftesa trfesa rtfesa fertsa efrtsa fretsa rfetsa erftsa reftsa terfsa etrfsa trefsa rtefsa ertfsa retfsa sterfa tserfa setrfa estrfa tesrfa etsrfa strefa tsrefa srtefa rstefa trsefa rtsefa sertfa esrtfa sretfa rsetfa erstfa restfa tersfa etrsfa tresfa rtesfa ertsfa retsfa asterf saterf atserf taserf staerf tsaerf asetrf saetrf aestrf eastrf seatrf esatrf atesrf taesrf aetsrf eatsrf teasrf etasrf stearf tsearf setarf estarf tesarf etsarf astref satref atsref tasref staref tsaref asrtef sartef arstef rastef sratef rsatef atrsef tarsef artsef ratsef trasef rtasef straef tsraef srtaef rstaef trsaef rtsaef asertf saertf aesrtf easrtf seartf esartf asretf saretf arsetf rasetf sraetf rsaetf aerstf earstf arestf raestf erastf reastf seratf esratf sreatf rseatf ersatf resatf atersf taersf aetrsf eatrsf tearsf etarsf atresf taresf artesf ratesf traesf rtaesf aertsf eartsf aretsf raetsf eratsf reatsf terasf etrasf treasf rteasf ertasf retasf steraf tseraf setraf estraf tesraf etsraf streaf tsreaf srteaf rsteaf trseaf rtseaf sertaf esrtaf sretaf rsetaf erstaf restaf tersaf etrsaf tresaf rtesaf ertsaf retsaf
Note: these 'words' (valid or invalid) are all the permutations of the word faster. These words are obtained by scrambling the letters in faster.