The developers of Ara: History Untold have published their 5th dev diary, this time talking about the eras in the game. The description from youtube reads the following:
Join our host, Steven Bell (@Stakuyi), and Lead Designer, Michael Califf, as they discuss the heart of Ara: History Untold and explore its fascinating progression system through its three Acts.
You can find this dev diary also on Twitter here, and you can join us for the discussion about Ara in the forum here.