Codes:

Level 2         VQVQFDE
Level 3         ICIGCAA
Level 4         ECPQPCC
Level 5         FTWKFEN
Level 6         HQWFTFW
Level 7         DWNDGBW
Level 8         JCJCJHM
Level 9         ICVGCGT
Level 10        LQPCUJV
Level 11        HNWVGKB
Level 12        FTQKVLE
Level 13        DCPLQMH
Level 14        EWDGPNL
Level 15        TCNGTOV
Level 16        TCVQRPN
Level 17        IQDNKQO
Level 18        KKKPURE
Level 19        NGOGKSP
Level 20        NNGWTTO
Level 21        LGWFGUS
Level 22        TQNGFVC