Most of the maps stopped working in 1.8 due to changes in game mechanics. That being said, the reason, I believe, the adventure lobby was shut down was because of the 1.8 update. Not to mention the 1.13 update completely changed the command block syntax. Anyways, after the 1.9 update, Simon made an announcement that he cancelled work on the third Herobrine map, stating that he wanted it to make the most of the current update, but updates were coming too fast which made it impossible to finish without being out of date. I always wanted it to be called Herobrine's Revenge. I believe that in late 2014, Simon, the owner of Hypixel was actually working on the third Herobrine map. The main reason I even played on the server was gone. Ever since then, I've always missed the adventure lobby. I would play the Herobrine maps all day, every day, until one day, the adventure lobby was just removed (I believe it was under maintenance for a while then just removed, but not sure on this). I found the adventure lobby, and it was all I would ever play. As a result of this, I joined the Hypixel server in January 2014. At the end of Herobrine's mansion, there was a sign that said you can play the map with other people online on the hypixel server. I played these maps with my friends and by myself all the time! The maps contributed to some of my best childhood experiences. My friends told me about the Herobrine maps, Herobrine's Mansion and Herobrine's Return.

Hypixel adventure maps down