riels irels reils erils ierls eirls riles irles rlies lries ilres lires relis erlis rleis lreis elris leris ielrs eilrs ilers liers elirs leirs riesl iresl reisl erisl iersl eirsl risel irsel rsiel sriel isrel sirel resil ersil rseil sreil esril seril iesrl eisrl iserl sierl esirl seirl rilse irlse rlise lrise ilrse lirse risle irsle rsile srile isrle sirle rlsie lrsie rslie srlie lsrie slrie ilsre lisre islre silre lsire slire relsi erlsi rlesi lresi elrsi lersi resli ersli rseli sreli esrli serli rlsei lrsei rslei srlei lsrei slrei elsri lesri eslri selri lseri sleri ielsr eilsr ilesr liesr elisr leisr ieslr eislr iselr sielr esilr seilr ilser liser isler siler lsier slier elsir lesir eslir selir lseir sleir
Note: these 'words' (valid or invalid) are all the permutations of the word riels. These words are obtained by scrambling the letters in riels.