Letter on position 1 (r) changed: 11 words bugs dugs fugs hugs jugs lugs mugs pugs tugs vugs yugs Letter on position 2 (u) changed: 3 words rags regs rigs Letter on position 3 (g) changed: 7 words rubs rucs ruds rues rums runs ruts Letter on position 4 (s) changed: 1 word ruga