?????????
      +----------
LNLNY | NTMGLMJYL
       -LNLNY
        =====
        QYZYJM
       -QMUMPV
        ======
         QNWYRJ
        -QQHQXZ
         ======
          QJHZGY
         -QUGRVT
          ======
           QMLMXL
          -QZLZZH
           ======
           ??????

base: 16
letters: GHJLMNPQRTUVWXYZ
difficulty: hard
attributes: excellent, long