????????
      +---------
PCPHL | XCYYMTNM
       -PCPHL
        =====
        CGNYTT
       - PCPHL
        ======
         ECNTLN
        -JLCMYG
         ======
          JCNHNM
         -MTLHYT
          ======
          ??????

base: 12
letters: CEGHJLMNPTXY
difficulty: medium