Just a good ole fashion isekai
This book is for the people who like to see an MC grind and grow. If you are into the minutiae, it may not be for you.
If something like reading about an MC eating a rabbit he killed but not explaining the process of skinning it and cooking it bothers you, then this is probably not for you.
The MC is summoned to a new world, and he is being hunted by people far stronger than him. About 90% of this book is about what he is doing to get stronger and how he is doing it.
His OP skills at 1st glance may seem minor, a small Stat boost, and a slight increase in leveling speed. But towards the end, it may seem more OP than originally thought.
Mc isn't OP in book 1 he still has Tiers to climb before he is anywhere near the threat he faces.
Overall, I thought it was a fun read. A lot of system Isekais get bogged down by trying to be too comedic or stressing minor, & boring details. This one just gets to the point.
P.S. MC is going for a rogue build, which will feature shadow skills from what I can see.