Is there a name for the trope where a story is high fantasy at first glance, except for it's not fantasy and is actually set in a post-apocalypse dystopian future?
I'm embarrassed to say that I have encountered this, this particular type of story on multiple occasions... So I got curious, is there a name to this trope?
The Mistborn era 1 (books 1-3) are fantasty magic.
Mistborn era 2 (books 4-7) occur hundreds of years later in that worlds “industrial/steam” age. Still, with magic.
So, for example, some allomancers can push or pull on metals. In Era 1 that’s used for combat but also for rapid movement. An allomancer can fall from a wall, throw a coin and “push” off of it causing them to bounce forward and upwards. As they’re starting to reach the azimuth they “pull” the coin, catch it and repeat.
They also in combat throw and then “push” coins or metal fragments like shrapnel.
In Era 2. A sheriff (who’s an allomancer) leaps across a gully, aims and shoots a bullet into a wooden crate and then “pushes” on it to cross it.
Another time during a shootout one “pushes” gunfire away so it deflects around him. Not guaranteed to get all of the bullets but useful in situations like that.
There are other uses and other allomantic abilities but the entire shift of the format was just done phenomenally.
you probably already know this, but for anyone else:
The Cosmere Series (of which the Mistborn Saga is a part of) does heavily feature Sci-Fi as well as post-apocalypse themes alongside (mostly) fantasy (Sci-Fi: the sunlit man, tress of the emerald sea; post-apocalypse: Stormlight Archives, Yumi And The Nightmare Painter), which made me think OP was talking about this series specifically.
In some of the other books it is mentioned that all of the powers originally came from a being called Adonalsium (basically God). what fuels all these manifestations of powers is called Investiture. Each Shard of Adonalsium manifests different Powers, Allomancy is just one of them.
so it's a unique mix of classic fantasy, sci-fi, and post-apocalypse genres in a single gigantic saga, in which the sci-fi and post-apocalypse themes are intentionally kept vague and in the background.
highly recommend all of the other books!
they are great in their own right, and also give a LOT of extra bits and peaces of the overall lore!
what's best about the series is, as you've already explained, the "hard-fantasy/sci-fi" approach to powers: all power requires some kind of source, everything comes from something.
best to do the Stormlight Archives after Mistborn (either order works), then the rest; order doesn't really matter, although i recommend Tress of the emerald Sea and The Sunlit Man to be read last, because they contain a lot of sci-fi lore, which is best enjoyed last (imho)
also: Stormlight Archives Book 5 is coming relatively soon, i think it's december?