One nerdy gripe that I have about the series is that the later in the series we get, the less accurate the depiction of the various gravities on different planets and moons.

In the first book, Red Rising, there are many references to the lower gravity on Mars, and Darrow is able to make leaps, and run in ways that just aren't possible in 1G. But by the time we get to Dark Age, it seems Pierce has forgotten all about the gravity differences. With so much time on Mercury, I don't recall any reference to the gravity there being very similar to Mars.

And Io and Luna have very low gravity, ~0.22G and ~0.18G respectively. The descriptions of the various fights on Luna don't make sense when you think about that low gravity. It's actually challenging to move around quickly in gravity that low. It's hard to get good traction on the ground to accelerate and stop.

Here's a fun video where they use a parabolic flight and simulate Mars Gravity:

https://youtu.be/xdJwG_9kF8s?t=191