Divine Shrines

If anybody has found one, do you remember where you found it? About how rare is it to find? I'm almost 37 hours in, cleared almost all of Merciless, and I have yet to find one. I found Echoing in Merciless Docks (which was the second-to-last one I needed), but haven't even heard of anybody finding a Divine Shrine.

Pretty sure I found mine in some random low level map, though I can not recall for sure.

What does the Divine Shrine do? There is no listing on the wiki.

I've only found one divine shrine and it took me 15 seconds of beating on the enemy to realize what it was. I grabbed it and read, "You are completely Invulnerable" and it clicked "Oh, that's why they wouldn't die..."

I found two in the same lunaris 3. And two more in lower level maps.
It's rare for sure, but not even close to Igna Phoenix in Anarchy from my experience.

[e] One in lunaris 2 as well

Ive found 2 of them. One was in lunaris

Found one... I think it was in merciless act1 submerged passage, but not 100% sure.

Are some shrines only in higher difficulties then?

130+ levels on multiple characters and I haven't found one. Done all kinds of Lunaris runs as well. Meh.

Found one divine in docks. Still missing the echoing. Done maybe 100+ docks maps so far.