You were made a defiant act against the gods of your world, weather they're real or not does not matter. Your very being was designed with profane methods, life forced upon dead matter and given the shape of something that looks like it's alive, but that no god will claim as theirs. Whatever form you take now is a mold you were squeezed into, your heart beats but no soul guides it. 

There is nothing after this world for you.

Ability Scores: You have +1 to Dexterity, Strength and Constitution, or must choose one to gain a +2 and drop another.

Feat: Don't Slow of Cease. With the looming knowledge, or at least gut feeling, that there is nothing beyond this mortal veil for you, your very being pushes past it's limits to cling to your profane existence before it's extinguished. When reduced to 0 hit points, once per long rest you can choose to enter a state of instinctual, unconscious rage, falling to 1 hit point instead. You are unable to use complex weapons or cast spells. You gain temporary hit points equal to a fourth of your total hit points, rounded up. You cannot communicate. You gain advantage on attacks against the creature that knocked you out.

Skill Proficiencies: You are proficient in Athletics and Acrobatics. You can also choose a proficiency between Religion and Arcana at your or the DM's discretion to better reflect the world.

Languages: You can pick between Primordial or Infernal to add to your known languages.