pexd epxd pxed xped expd xepd pedx epdx pdex dpex edpx depx pxde xpde pdxe dpxe xdpe dxpe exdp xedp edxp dexp xdep dxep
Note: these 'words' (valid or invalid) are all the permutations of the word pexd. These words are obtained by scrambling the letters in pexd.