We were I think 8 or 9. We got access to an onion forum on Tor with randomized nicknames, and one person who said they were a representative of a bigger network, but no extra info was given. Then they told us to find some common project to work on; something that would change the world or whatever. We were supposed to discuss ideas and decide by ourselves. Eventually we settled on an idea and started working on it, but we had a shitty forum, a shitty chat, and an even shittier slow git repo. The whole thing was pointless so I just drifted away (it was a very busy time for me).
It made no sense, there was no reason why we should work in secrecy, no infrastructure, no motivation, nothing. I bet the guy who said he was a representative was just a kid somewhere who made up the challenges. I don’t know, I just abandoned it and lost the drive to pursue any further ARG after that.