XHN
      +---------
TLLQE | UUHULFNF
       -UELPHT
        ======
         FEPRUN
        -FELEFT
         ======
           PYFHF
          -TLLQE
           =====
           NYYRX

base: 12
letters: EFHLNPQRTUXY
difficulty: medium
restrictions: no multiplication