Steam: What is the Mysterious Badge For? - Overmental

If you've checked your Steam Badges page recently, you might have noticed a weird new addition at the top: the "Mysterious" badge. Don't worry, you're not
If you've checked your Steam Badges page recently, you might have noticed a weird new addition at the top: the Mysterious badge. Don't worry, you're not going crazy, they appeared earlier this month

News - Steam Community Announcements

Miscellaneous For Sale, Buy Online

I was checking someone's profile and I saw these badges. Is this posible? Look at the levels and xp. : r/Steam

Mysterious emblem, Old School RuneScape Wiki

The Cantuarian November 1890 - June 1892 by OKS Association

AD&D - Faiths & Avatars (2e) - Flip eBook Pages 51-100

Seasonal Badges haven't been updated in 6+ months. Why? : r/Steam

Mysterious emblem, Old School RuneScape Wiki

Fifty Years in Wall Street