TVV
      +--------
MHTPW | HGRZYGN
       -MHTPW
        =====
        XYLJVG
       -XLUXYP
        ======
         XYRXLN
        -XLUXYP
         ======
          XJGVW

base: 16
letters: GHJLMNPQRTUVWXYZ
difficulty: hard
missing: Q