Levelcodes:

 Level  3:  GGMC
 Level  6:  WBRD
 Level  9:  QDFZ
 Level 12:  ZBBM
 Level 15:  ZCRB
 Level 18:  RCGD
 Level 21:  SBNG
 Level 24:  NBTC
 Level 27:  KFNG

by Kevin J.