FTGQ
      +---------
MQWWM | WGTLNGMM
       -QNGUR
        =====
        YMTGFG
       - GGHYL
        ======
         MRWMMM
        -MTEGRU
         ======
          YQMWHM
         -YTYWTY
          ======
           MEGGY

base: 13
letters: EFGHLMNQRTUWY
difficulty: intermediate
restrictions: no multiplication