This year's objects with symbols were the "Forest Guardians." Symbols this year represented progress toward "waking up" a dormant forest guardian. The majority of symbols were trivia riddles, but a few were "collections" that could be unlocked by contributing enough of a certain item.
Fantasy Forest Guardian
Sci-fi Forest Guardian
Non-fiction Forest Guardian
Lore Wiki » Epic Weeks » Epic Week 2016 » Gameplay » Forest Guardians