Are there any current religions, except Christianity, which is based upon human deification? The ancient Greeks and Romans did it and I presume that's where Christians got the idea.
It seems that many of the deities in mythology were the products of euhemerism/deification. and, most likely, a damned sloppy use of the language perhaps that is what we have with Odin's great grey horse Sleipnir. "that horse was so fast it was like he had 8(or 6) legs" and eventually we have a six/or eight legged horse--- (of course Sleipnir's mother was Loki- a shapeshifter---so, who knows?)
Depends on how "deified" we're talking here. Where's the line between an ancestor's spirit and a minor god? Yes and no. It's complicated.
that really depends on your definition of human deification (or Apotheosis) there are some that consider Buddha deified, and there are always cults to consider (Sun Myung Moon immediately comes to mind here) Here is an article that is related to the topic: "Psychology of attraction to religious deities and super-heroes" https://www.sciencedaily.com/releases/2019/09/190930101003.htm the study is linked, or you can go here: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0220886 You ain't kidding!
The angle on philosophy that near death experiencers come back with adds a whole new level to the idea of us being made in the image of YHWH. Christian Andreason, chapter two.... http://www.allaboutchristian.com/spirituality/