I Sacrificed Myself, and a God Pulled Me Out

I was once the strongest in the world, guarding the frontier for the human race for over a decade.

But as terrible news from beyond the border arrived, my only family member died.

They died because of the human race's scheme against the other races.

I swore to repay blood with blood. After using an ancient secret technique, the other races were wiped out, and the blood debt was paid in full.

I should have died, but instead I was reborn. Yet it seems history cannot be changed!

I die and come back to life, live and die again... Reincarnation?