???????
      +--------
LJGJM | PUTLUPR
       -TXHUN
        =====
        JWLUNP
       -WRGMTJ
        ======
         WTMUTR
        -WTNNGH
         ======
         ??????

base: 13
letters: GHJLMNPQRTUWX
difficulty: medium
attributes: good indirection, state table
missing: Q