YYR
      +---------
GTNGE | GTXYPXHX
       -RLHXQQ
        ======
         RFFUNH
        -RLHXQQ
         ======
          HGFLGX
         -HEXGEF
          ======
           HPXTH

base: 13
letters: EFGHLNPQRTUXY
difficulty: medium
restrictions: no multiplication