Board Thread:General Discussion/@comment-173.77.201.101-20141209004257/@comment-3250527-20141209004747

As for the light volumes, the Murder Mystery "mini-arc" (Episodes 5-6) appears in Volume 8, which is another collection of side stories. The anime changed a lot in Murder Mystery.

You won't miss a lot. SAOII did its best with keeping in compliance with the plot, but there are still a few discrepancies. Each of those adaption notes are found on each episode page.

It is likely for the appearance of a Season 3, but it is not confirmed. We'll see when SAOII's finale episode happens, or if there's an announcement of another special episode (like Extra Edition).