Board Thread:General Discussion/@comment-34924658-20170828191655/@comment-31231929-20170828223104

Hyde was the secondary villain up until episode 4 (Jekyll was revealed to be a villain in that episode so him and Hyde shared secondary villain status for that episode), The EQ was the main villain for episodes 2-10, then again in 14. Gideon was the main villain in episodes 11-16, then Fiona was the main for the rest of the season. Rumple could be considered a secondary villain for 6A.

For 5A, I'd say the main villain is the Dark One, and the secondary villains are Arthur and Zelena.