The Lost Metal is the sixth book in the Mistborn series and the fourth and final book in the Wax and Wayne subseries, the so-called "Era Two".
I tore through this one quickly, finishing it in about a week. It has a bit more of a sci-fi action thriller feel than just pure fantasy, which is fine; one of the themes in Era Two is apparently the technological advancement of Scadrial and that directly affects how they are viewed by other entities in the Cosmere.
Speaking of Sanderson's Cosmere, this book is chockful of references to the greater Cosmere. While the last book felt like it expanded into Scadrial's greater history, this book expands the Mistborn story to include the influence of the greater Cosmere as well. The Cosmere references are a bit of a double-edged sword; they're fun when you get the references, but you can get a bit lost if you don't appreciate them. For me, it left me wanting to know more and read up on his other Cosmere books.
I did enjoy the general plot of the film and where it brought the character arcs for the main cast. Wayne got a fitting end, especially given that he felt like the least developed of the cast after the first three books. I also really like where Marasi and Steris landed. Wax is just ok lol. This book felt like an appropriate end to wrap up Era Two and at the same time set the stage for further adventures down the line on Scadrial.
I am also a bit happy that these books were much shorter in length compared to Mistborn Era 1 and Stormlight Archive, because the tendency for those kinds of epic-length books is that because I read relatively quickly and urgently want to advance the plot I can often miss details or forget them later on years after reading the books. For example, while I do remember Kelsier, Sazed and Marsh from Era 1, I don't remember enough of what their characters were like because those books had many more characters to get to know and the cast expanded rapidly throughout the series. For Era 2, the books maintained a tight focus around the four main characters from start to end, making them a bit more memorable for me I think. We shall see how much of them I remember down the line!
That being said, it could be fun to re-read all the Mistborn and SA and other Cosmere books down the line when I can really digest them all and appreciate all the references, although that might take forever!
This will likely be my last fiction book for the year. Looking forward to more reading next year!