QRP
      +--------
LWLNG | YYLQYLR
       -QHQPN
        =====
         FXNXL
        -HXFFG
         =====
          TPYUR
         -TJJQN
          =====
           PYWQ

base: 15
letters: FGHJLMNPQRTUWXY
difficulty: hard
missing: M