?????????
      -----------
YQYUF ) MXTRFQLWN
       -MPNXP
        =====
         TUMFQ
        -TUXFP
         =====
           TPQLW
          -QXTYX
           =====
            MRXUN
           -MPNXP
            =====
            ?????

base: 12
symbols: FLMNPQRTUWXY
difficulty: medium