LQMJ
      +---------
UJQHQ | YWNFNQPF
       -YGURL
        =====
         RMLTQ
        -UJQHQ
         =====
         LFQLXP
        -LYXURM
         ======
          QXWPWF
         - WQYHJ
          ======
           LTUUU

base: 15
letters: FGHJLMNPQRTUWXY
difficulty: medium