Letter on position 1 (f) changed: 11 words bugs dugs hugs jugs lugs mugs pugs rugs tugs vugs yugs Letter on position 2 (u) changed: 4 words fags fegs figs fogs Letter on position 3 (g) changed: 6 words fubs fuds fums funs furs fuss Letter on position 4 (s) changed: 1 word fugu