My favorite eLearning Heroes Challenge last year was #432 escape room. Demo:
https://zkelearningchallenges.s3.amazonaws.com/escape+the+music+room/story.html This challenge gave me an opportunity to play with the 360 degree picture feature which I had never used before, and to make a "notes" feature using variables that collected answers for the user when they came up with them.
It probably took me around 6-8 hours to put together, but there were a lot of starts and stops as I worked on this in between other thigs. It was a great learning experience as it challenged me to solve some problems using variables in ways I never had before, so I really enjoyed that.
One thing I didn't love about the 360 feature is that the green hotspots are visible to the player when they click on them, hopefully that's something that's on Articulate's backlog to fix.