arobf raobf aorbf oarbf roabf orabf arbof rabof abrof barof rbaof braof aobrf oabrf aborf baorf obarf boarf robaf orbaf rboaf broaf obraf boraf arofb raofb aorfb oarfb roafb orafb arfob rafob afrob farob rfaob fraob aofrb oafrb aforb faorb ofarb foarb rofab orfab rfoab froab ofrab forab arbfo rabfo abrfo barfo rbafo brafo arfbo rafbo afrbo farbo rfabo frabo abfro bafro afbro fabro bfaro fbaro rbfao brfao rfbao frbao bfrao fbrao aobfr oabfr abofr baofr obafr boafr aofbr oafbr afobr faobr ofabr foabr abfor bafor afbor fabor bfaor fbaor obfar bofar ofbar fobar bfoar fboar robfa orbfa rbofa brofa obrfa borfa rofba orfba rfoba froba ofrba forba rbfoa brfoa rfboa frboa bfroa fbroa obfra bofra ofbra fobra bfora fbora
Note: these 'words' (valid or invalid) are all the permutations of the word arobf. These words are obtained by scrambling the letters in arobf.