????????
      +---------
NEXQX | XGYXNQQT
       -NEXQX
        =====
         TXRTQ
        -MMFQY
         =====
          GUEGQ
         -XQYGE
          =====
          NPTPET
         -NPGPGJ
          ======
          ??????

base: 13
letters: EFGJMNPQRTUXY
difficulty: medium