ildsu lidsu idlsu dilsu ldisu dlisu ilsdu lisdu isldu sildu lsidu slidu idslu dislu isdlu sidlu dsilu sdilu ldsiu dlsiu lsdiu sldiu dsliu sdliu ildus lidus idlus dilus ldius dlius iluds liuds iulds uilds luids ulids iduls diuls iudls uidls duils udils lduis dluis ludis uldis dulis udlis ilsud lisud islud silud lsiud sliud ilusd liusd iulsd uilsd luisd ulisd isuld siuld iusld uisld suild usild lsuid sluid lusid ulsid sulid uslid idsul disul isdul sidul dsiul sdiul idusl diusl iudsl uidsl duisl udisl isudl siudl iusdl uisdl suidl usidl dsuil sduil dusil udsil sudil usdil ldsui dlsui lsdui sldui dslui sdlui ldusi dlusi ludsi uldsi dulsi udlsi lsudi sludi lusdi ulsdi suldi usldi dsuli sduli dusli udsli sudli usdli
Note: these 'words' (valid or invalid) are all the permutations of the word ildsu. These words are obtained by scrambling the letters in ildsu.