????????
      +---------
XLXYG | FGLYPPPX
       -XLXYG
        =====
         LPHQP
        -XLXYG
         =====
         PXXFQP
        -PMGHWF
         ======
          XPLWFX
         -WLPYQX
          ======
          ??????

base: 11
letters: FGHLMPQTWXY
missing: T
difficulty: medium