Waking up in the body of a Necrontyr, the moment he undergoes biotransference is not how the MC imagined reincarnation. The MC does not know how he got there, or how he deserves this fate, all he does know is that he is now a Necron Lord and that he was given a special gift, the Essence of the Machine.
Armed with nothing but that incredible power and his burning anger and wish for revenge, Hasyn who has lost his soul and therefore his free will and most of his ambitions, slowly becomes Hasyn the Relentless, the mightiest of the Necron.
All alone in this new Universe, he must ask himself, whether he should stay in Warhammer 40k where he has those who are like him, or leave to discover new universes.