MTL - The Strongest System - Chapter 1 Let me upgrade

Upon meeting the girl who would become her adopted younger sister, the duke’s daughter Christina regained memories of her previous life. Through those memories, she learned that her new sister, Mishuli, was the heroine of a certain story. And though the story depicted a Christina who abused her sister, the real Christina turned into a siscon who spoiled Mishuli to no end.

This is a very serious Xianxia book, but why the introduction I always want to describe it as: My second child is a giant, and there will be something going on in the future, and so on.

In short, you will understand after reading it, this is really not the YY of male species, what is missing, what is missing, etc. I am telling the truth.

- Description from novelbuddy

In the twenty-ninth year of the First Emperor, Bo Langsha was attacked.

When Ying Zheng merged the memories of the 21st century history doctor, looked at the mighty mountains and rivers in front of him, and said to himself, “In this life, my Daqin can’t die!”

- Description from novelbuddy

I was reincarnated into another world, and I’ve brought the Horadric Cube from Diablo II with me.
Being a knight is cool and all, but being a wizard is pretty neat as well.
So, which one will it be?