SLOWLY, OVER MANY YEARS.
By having tiny little robots working on your insides, slowly cutting off little pieces and destroying them, pieces so small the body thinks it can repair but loses more before it does.
each of the robots giving shocks each time it destroys a piece, 100,000sss of robots making you scream in agony every minute of every hour of every day till you die by turning inside out and nothing but dust exploding from your shocked and sliced arteries and veins. the robots expelling and tearing new orifices into your body and ripping them as they leave. Finally, a bath of vinegar, soaking into the wounds as you draw your last breath, waking to find your on a machine, keeping you alive, though you cannot do a thing. holding your body in suspended animation while it eats itself and you suffer without even being able to cry.
Hows that?