someone on reddit made some secret subreddits for certain acievements:
- controversial club - one of the most controvertial posts on reddit within an hour
- popular club - top 25 posts on reddit of the day
- eternity club - popular club clone
- ternion club - popular club but you also got ternion
etc…
why they exist? who knows, but i guess they are no longer secrets
I was part of eternity club before i deleted my account. Never really used it though.