NQFG
    +-------
RRM | GLFTLH
     -NUG
      ===
       WLT
      -QYH
       ===
        TML
       -TWY
        ===
         JHH
        -JPN
         ===
          HY

base: 15
letters: FGHJLMNPQRTUWXY
difficulty: hard
missing: X