???????
     ---------
XLFE ) GQYHNFQ
      -JQWP
       ====
       PWYEN
      -QTEWG
       =====
        QTLQF
       -QFWLX
        =====
         XFEQQ
        -XQGNY
         =====
         ?????

base: 13
symbols: EFGHJLNPQTWXY
difficulty: medium