Biomechanic

 Something between a surgeon, an engineer, and a mad scientist, biomechanics integrate the study of artifice with that of humanoid biology. They use their vast knowledge of both subjects to supplement their own bodies with powerful artificial augmentations, turning themselves into anything from machines of war to covert operatives. Whatever their specialty, the body of a biomechanic is an ongoing experiment subject to constant innovation.

Bonus Proficiencies

 You gain proficiency in the Medicine skill, and with smith's tools. If you already have this tool proficiency, you gain proficiency with one other type of artisan's tools of your choice.

Biomechanic Spells

You always have certain spells prepared after reach particular levels in this class, as shown in the Biomechanic Spells table. These spells count as artificer spells for you, but they don't count against the number of artificer spells you prepare.

Level	Spell
3rd	false life, thunderwave
5th	gentle repose, pass without trace
9th	lightning bolt, nondetection
13th	death ward, greater invisibility
17th	mislead, modify memory

Bionic Arm

 You have replaced or otherwise augmented your arm with magical technology, and can use it as a spellcasting focus for your artificer spells. Unarmed strikes with it deal 1d6 bludgeoning damage, and you can use your Intelligence modifier for its attack and damage rolls. In addition, you can choose a form for your bionic arm to take. You can spend a bonus action to retool your arm to a different form, which you can do a number of times per short or long rest equal to your proficiency bonus.

 Grappleclaw Launcher. You can make unarmed strikes as a ranged attack with a range of 20/60 feet. In addition, as an action, you can choose an unoccupied space adjacent to a surface you can see within the weapon's short range. You fire your grappleclaw to the adjacent surface and zip through the air directly to that space.

 Retractable Saw. You can use a bonus action to extend or retract a sawing mechanism from your bionic arm, which deals 1d10 slashing damage on unarmed strikes, replacing the regular attack with your bionic arm.

 Tool-Tuned Digits. You can use your arm as thieves' tools or a set of artisan's tools of your choice which you make check at advantage with, and can use your Intelligence modifier to make checks with it.

Supplemental Prosthetic

 Thanks to your exceptional artifice, you have augmented your body in unique physical ways. When you reach 3rd level in this specialisation choose two supplemental prosthetics to gain the benefits of, and you gain another at 6th, 9th and 15th level. You cannot choose the same supplemental prosthetic multiple times. When you gain a level in this class, you can change a supplemental prosthetic you have with another from this list. 

 Adamantine-Fused Skeleton. Any critical hit against you becomes a normal hit.

 Cranial Memorybank. You can prepare additional artificer spells equal to your proficiency bonus.

 Featherlight Footsteps. Your speed increases by 5 feet and your jump distance is doubled.

 Hoverpad Heelplants. You gain a fly (hover) speed equal to 5 times your Intelligence modifier, but you fall if you end your turn in the air and nothing else is holding you aloft.

 Medicardio Pump. When you roll Hit Dice to regain hit points, you regain an additional number of hit points equal to your Intelligence modifier (minimum of one).

 Noxguard Respirator. You can breathe air and water, and are unaffected by effects that act on your respiratory system, such as the stinking cloud spell.

 Ocular Scopolenses. You can see up to a mile away with no difficulty, able to discern even fine details as though looking through at something no more than 100 feet from you. You also gain advantage on Wisdom (Perception) checks that rely on sight.

 Olfactory Enhancements. You have advantage on Wisdom (Perception) and (Survival) checks that rely on smell, and on checks to identify components in a substance using your nose. 

 Piston-Fibre Muscles. Your carrying capacity (including maximum load and maximum lift) is doubled, and you can use Intelligence in place of Strength for checks made to push, pull, lift, or break objects.

 Reinforced Exoskin. When you aren't wearing armour, your AC is 13 + your Dexterity modifier. You can also use your reinforced exoskin to determine your AC if the armour you wear would leave you with a lower AC. You can use a shield and still gain these benefits. 

 Shock-Absorber Joingrafts. When you fall, you can use your reaction to reduce any falling damage you take by an amount equal to five times your artificer level.

 Verbaflex Voicebox. You can mimic sounds you have heard, including voices. A creature that hears the sounds you make can tell they are imitations with a successful Wisdom (Insight) check opposed by your Charisma (Deception) check. You can make this check with your Intelligence modifier instead of your Charisma modifier.

Supercharged Arm

 Starting at 5th level, you can attack twice, rather than once, whenever you take the Attack action on your turn.

 Additionally, your bionic arm can power up your attacks and spells. When you make an attack with your bionic arm, an attack with a weapon held in your bionic arm, or when you use your bionic arm to cast a spell with an attack roll, you can increase the damage dealt to a target by a number of d4s equal to your proficiency bonus. Once you use this feature, you must finish a short or long rest before you can use it again.

Body Autoregulation

 Beginning from 9th level, you have carefully balanced the mechanisms of your body, allowing it to regulate itself and operate at peak efficiency. You have advantage on saving throws against disease and poison, and you gain resistance to poison damage. You also cease to visibly age, your lifespan, and you no longer suffer the fragility of old age.

Neuroenhancements

  Starting at 15th level, you have developed neural implants that ensure a minimum cognitive ability at all times. When you make an Intelligence or Wisdom check, treat a roll of 9 or lower on the d20 as a 10.
 Your implants also allow you to better resist outside influences on your mind. You gain proficiency in Wisdom saving throws.