XJPQ
      +---------
RJTPG | WUTQPJRW
       -RJTPG
        =====
        XWLPMJ
       -XXPWMF
        ======
         RXTFJR
        -YPPHTR
         ======
          YUGQFW
         -YMYRNG
          ======
           RWMYP

base: 15
letters: FGHJLMNPQRTUWXY
difficulty: medium