Yanaxulap's Cave is an ancient, prehistoric cave that serves as a place of worship for Yan and used to be the home of Yan before he fled to the Mega Void. It is a greyish black cave surrounded by boulders, with a few yellow lights and many paintings featuring Yan and the Illuminati Pyramid.
To worship Yan, say his name five times, then say "ALL HAIL THE ONE AND ONLY GOD!" You must then sacrifice a body to him.
It is also a Roblox game made by Roger and can be found here: https://www.roblox.com/games/359483114/Yanaxulaps-Cave