Mrs. and Mr. Smith - Chapter 995 - Drexel Takes Action_1

Our protagonist Caam is a man from Earth that was reincarnated into this world as a demon. In order to survive, he spared no effort in avoiding the sparks of battle and without noticing it, he became strong himself.

I made a game.

Emperor Xianwu ninth reincarnation, only to break through the shackles, was besieged and killed by masters from all walks of life.

Fortunately, a ray of divine consciousness traveled across thousands of planes to the earth and entered the body of the dead young man, just to get rid of the anger in his heart and to regain that peerless peak!

- Description from MTL

Jacob Steve, an Old Man, died at 116 after living a whole life.

But Jacob always had a dark side, which he always suppressed and hid from others.
However, in the later years of his life, when death was inevitable, he understood there wasn't any point in having wealth, knowledge, or desires if you couldn't have a life to enjoy them.

He became obsessed with fabled immortality and devoted his reaming life to extending his fleeting lifespan, but just like any other failed.

However, he mysteriously got another chance at life and found a way that led to fabled immortality.
But he was also forewarned that the way led to it was filled with blood and darkness!

In the end, Jacob chose it anyway with no way of going back, and it was also the start of his suffering and his icky, brutal journey toward the 'Immortality' he wanted so badly!