Episode I(July 3, 2015) Episode X Episode XX Season 1; Volume 2: Middle Ages(4 episodes) Episode II(July 3, 2015) Episode VI Episode XII Episode XVIII Season 1; Volume 3: Renaissance(4 episodes) Episode V Episode VIII Episode XIII Episode XXI Season 1; Volume 4: Industrial Revolution(5 episodes) Episode VII Episode IX Episode XV Episode XVII Episode XXII Season 1; Volume 5: Western Times(5 episodes) Episode III(July 3, 2015) Episode XI Episode XIV Episode XIX Episode XXIII Season 1; Volume 6: Future!!!(5 episodes) Episode IV(July 3, 2015) Episode XVI Episode XXIV Episode XXV Episode XVI