biffy ibffy bfify fbify ifbfy fibfy biffy ibffy bfify fbify ifbfy fibfy bffiy fbfiy bffiy fbfiy ffbiy ffbiy iffby fifby iffby fifby ffiby ffiby bifyf ibfyf bfiyf fbiyf ifbyf fibyf biyff ibyff byiff ybiff iybff yibff bfyif fbyif byfif ybfif fybif yfbif ifybf fiybf iyfbf yifbf fyibf yfibf bifyf ibfyf bfiyf fbiyf ifbyf fibyf biyff ibyff byiff ybiff iybff yibff bfyif fbyif byfif ybfif fybif yfbif ifybf fiybf iyfbf yifbf fyibf yfibf bffyi fbfyi bffyi fbfyi ffbyi ffbyi bfyfi fbyfi byffi ybffi fybfi yfbfi bfyfi fbyfi byffi ybffi fybfi yfbfi ffybi ffybi fyfbi yffbi fyfbi yffbi iffyb fifyb iffyb fifyb ffiyb ffiyb ifyfb fiyfb iyffb yiffb fyifb yfifb ifyfb fiyfb iyffb yiffb fyifb yfifb ffyib ffyib fyfib yffib fyfib yffib
Note: these 'words' (valid or invalid) are all the permutations of the word biffy. These words are obtained by scrambling the letters in biffy.