The end game is described in this short story: https://gwern.net/doc/fiction/science-fiction/1995-egan.pdf

Either that, or something nasty like the Gonchong from the Fighting Fantasy book series Island of the Lizard King.

I would post a link, but the only standalone topic page is on a Fandom site, which counts as doubly morbid.

Who is the author?

Greg Egan. It’s in his excellent short story collection “Axiomatic”.

Why do people think we're going to live forever. We hardly understand anything about the body.

[dead]

[dead]