LNUR
      +---------
RVZNQ | GPHHXNLP
       -JXMUY
        =====
        VNVRXN
       -VJVYMY
        ======
         VYVNNL
        -WGQTWY
         ======
           UXHLP
          -XPLMQ
           =====
           WVQQG

base: 16
letters: GHJLMNPQRTUVWXYZ
difficulty: hard