Found a Bizarre Invitation in a Transylvanian Library... Anyone else seen anything like this?

Hey everyone,

I just had a really weird experience while traveling in Romania. I was browsing a small library in a tiny town nestled in the Carpathian Mountains, and I found this invitation tucked inside a book. The thing is, it was stamped with some kind of sigil, a wax seal, but the strangest part was that it also had a QR code printed on it. Talk about an odd mix of old and new.

Naturally, I scanned the QR code. It led to a riddle. Once I solved it, the link took me to a website called gnosisarcanum.org, and it asked for an invite code.

Has anyone else stumbled across anything this peculiar? A physical invitation with a digital puzzle leading to a website? It feels like the start of something... I'm tempted to explore, but wanted to see if anyone else has encountered anything similar before diving in.

Let me know if this rings any bells for anyone!