This is a nice twist on an gaming isekai, as not only does the MC get melded into one of the game characters (Erhin Eintorian) of the military strategy game that he was an expert in, he has complete access to the gaming system that works just the way it did when he played the game, including the ability to level up and acquire skills by defeating enemies. He starts out with the foreknowledge of the game and it's characters, which allows him to literally able to run circles around his enemies. However, once he starts making moves that are outside ofthe game parameters, it causes a bit of a butterfly effect, which changes the future. However, while he may only be middle strong at first, physically, he is mentally OP and the changes that occur allow him to play the game in a whole new way that is outside of what he had experienced before.

One of the better things in this LN is the excellent character development in it. The author spends a good bit of time on each of the main supporting characters, both those that support the MC, as well as some of his more prominent enemies. It's done so well that, even after he collects a good plethora of retainers, they are very easy to remember who they are, since you've already gotten to know them quite well.

Definitely recommend this one, as there really never is a dull moment in the read.