XLG
      +---------
PMXHW | XETXXTLM
       -GTJMNQ
        ======
         TMRNJL
        -TLQXHT
         ======
          GRPMGM
         -NLHJRL
          ======
           PNXPX

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