LMRF
      +---------
NFFNW | JUNYYFLP
       -WWLJG
        =====
         XXLYF
        -XPWYM
         =====
          RQTHL
         -RPPRY
          =====
           LWJPP
          -LRNLM
           =====
            FWRT

base: 15
letters: FGHJLMNPQRTUWXY
difficulty: hard