????????
      +---------
WQYYW | PTXEUWET
       -PWGMQ
        =====
         UXLPW
        -WQYYW
         =====
          YRGRE
         -PWGMQ
          =====
           LGJWT
          -YMYJE
           =====
           ?????

base: 13
letters: EGJLMPQRTUWXY
difficulty: hard