????????
     +---------
UENE | NXHNPUPN
      -NXUTN
       =====
         PNEU
        -UENE
         ====
         NXNHP
        -NUXXX
         =====
          UETHN
         -UTXNP
          =====
          ?????

base: 7
letters: EHNPTUX
difficulty: intermediate