50000 Users Bookmark is a tag used for illustrations with more than 50,000 bookmarks. It is a tag rarely used, and usually given to illustrations so good, that 10 points are not enough for it.
Currently there are 5 illustrations with 50,000 bookmarks, as well as an approximate number of 11 illustrations reaching 40,000+ bookmarks. Even with 50,000 bookmarks set as a borderline for god like illustrations, it won't look far fetched.