A biomechanical race of living constructs hailing from Mechanus.  RACIAL TRAITS Ability Score Increase: +2 Intelligence Axomatic Mind : You have advantage on saving throws vs. charms and illusions, as well as an eidetic memory.    Biomechanical Body : Any lightning damage that a mechanatrix takes that does not exceed its Constitution score is converted harmlessly into temporary hit points. 5 of these temporary hit points can be spent to cast shocking grasp, 10 can be spent to hurl a ball of lightning (1d10 lightning damage, Dexterity save for half damage), and 15 can be expended to move 30 feet as a reaction when attacked. Clockwork Heart : Your heart is a machine that will run endlessly and perfectly until it is destroyed. When reduced to 0 hp, you can continue to act normally until you fail your first death save at which point you may no longer take move actions, once you fail your second death save you may no longer take any further actions. Living Construct : You are a living construct. You don't need to eat, drink, breath, or sleep, but you can ingest food and drink if you wish.You're immune to poison, sleep effects, paralysis, disease, nausea, fatigue, exhaustion, effects that cause the sickened condition, and life drain. Unlike other constructs, mechanatrix have organic components which are subject to critical hits, nonlethal damage, stunning, ability damage, ability drain, and death effects or necromancy effects. However a  mechanatrix is not immune to the mind-affecting spells and abilities of the mentioned conditions. You also gain the full benefits of the spending of hit dice at the end of a short rest, and the full effects of a long rest after using a repair kit for that time period. Subraces: Ineffable and Modronoid.