upend puend uepnd eupnd peund epund upned puned unped nuped pnued npued uenpd eunpd unepd nuepd enupd neupd penud epnud pneud npeud enpud nepud upedn puedn uepdn eupdn peudn epudn upden puden udpen dupen pduen dpuen uedpn eudpn udepn duepn edupn deupn pedun epdun pdeun dpeun edpun depun upnde punde unpde nupde pnude npude updne pudne udpne dupne pdune dpune undpe nudpe udnpe dunpe ndupe dnupe pndue npdue pdnue dpnue ndpue dnpue uendp eundp unedp nuedp enudp neudp uednp eudnp udenp duenp edunp deunp undep nudep udnep dunep nduep dnuep endup nedup ednup denup ndeup dneup pendu epndu pnedu npedu enpdu nepdu pednu epdnu pdenu dpenu edpnu depnu pndeu npdeu pdneu dpneu ndpeu dnpeu endpu nedpu ednpu denpu ndepu dnepu
Note: these 'words' (valid or invalid) are all the permutations of the word upend. These words are obtained by scrambling the letters in upend.