User blog comment:E1l8f2/the strange things in ac/@comment-5088097-20120530000050/@comment-4829046-20120530085524

To be honest I never noticed that they skipped Sequences 12 and 13 cause my version of AC II is different so I had to complete Sequences 12 and 13 before I went to Sequence 14. (Also any true gamer would have found all the codex pages before being told to collect them to advance a sequence, since we pros love to collect and do everything 100%)