It was just OK. I’m glad I didn’t take the deal to buy the whole series. It had potential for me, as I love the “ancient alien artifact” trope, but this book was disappointing. The speculative science and engineering was sketchy and at times completely unbelievable. For example, magic space/diving suits which work over a huge pressure range but still can be easily punctured to kill the wearer. Gravity seems to be whatever is convenient– the surface gravity on Enceladus is like 1/100g and yet they walk around and have fist fights. I’m guessing the author is not a scientist or engineer, and didn’t bother to do his homework. The dialog was immature and repetitive.
I finished the first in the series but will probably give the others and other works by this author a miss.