There are two broad categories of augmentations in our world. One is the addition of knowledge or cybernetic parts, ie, a limb, an eye, or a module that installs knowledge wholesale. The other is neurachem, which augments the brain, perception, reflexes, etc, in short bursts. There is also muscle memory, which is not an augmentation but something innate to a sleeve.

Cybernetic Implants

Just about every body part can be replaced with a robotic one. The more obvious the modification, the cheaper it is. The most expensive are completely hidden except to scans or medical examinations. Cybernetic modifications also include coating bone with metal for increased durability, or a scanning device implanted in an eye. Cybernetic implants can also help with mathematical capacity or to give someone more control in virtual space.

** EXAMPLE IMPLANT TYPES**

Enhanced Bone Density Enhanced Muscle Strength Metal Skull Plating
Cybernetic Limb Cybernetic Eye(s) Bionic Ears
Reinforced Spine Mathematics Booster Enhanced VR Jack

COMBAT ENHANCEMENT BUNDLES

Combat Enhancement (Minor): Reinforced points of weakness such as jugular, solar plexus, forearms (for blocking.) Fine mesh over skin to better protect against melee strikes and sharp objects.

(There are bundles beyond minor, but they are not available out of chargen. You may be able to purchase a higher upgrade through XP. See Upgrades).

Modules

People can purchase skill and knowledge upgrades to augment their stacks. These modules are most often used when someone needs to learn something quickly. However, there are various limitations to the technology. Something like a new language is a fairly common module.
People don't tend to install modules for combat knowledge because it does not come with the requisite physical conditioning or muscle memory. It would be like having a manual of martial arts downloaded into your head without any physical training. The only time someone might install a combat module is if they are spun up into a combat sleeve without any combat training of their own.
The general rule of thumb with modules is, if it involves something physical, the modules either don't exist or they are rarely used. Modules are moderately expensive (generally more expensive than taking a course and learning the old fashioned way), so people only tend to purchase them when they need to learn something quickly. Too many module installs in a short period of time can cause headaches and disorientation. The human mind can only take so much of an infodump at a time.

MODULE EXAMPLE TYPES

A Language Combat Knowledge (Academic) A Skill

Neurachem

Neurachem affects reflexes, perception, spatial awareness and reaction time. Unlike cybernetic implants that are always there, and modules, which create an infodump, neurachem is short-acting. Some neurachem is triggered automatically in response to certain stimuli, while other types can be triggered with concentration.
Neurachem essentially acts as turbo boost for certain stats. When enhanced reflex neurachem is used in combat, time slows down for the person with it, allowing them to more carefully read the scene and plan lightning fast blows. When perception neurachem is activated, the user can perceive far more about their surroundings than a person normally would. They can read very subtle body language, or they may pick up scent or spot something they otherwise wouldn't. It can also be used to temporarily boost intelligence, charisma or any other attribute.

There are different grades of neurachem:

Consumer-grade neurachem only provides short bursts of increased reaction or perception, lasting a few minutes at most. It comes with very few adverse effects. Generally only two attributes (sets of neurachem) can be triggered at once.

Military-grade neurachem can last for hours and boost multiple attributes at once. Only those with extensive and decorated military service would have access to this kind of neurachem, and sometimes the potency is dialed down upon return to civilian life.

Black market neurachem is the former two types of neurachem hacked and modified. Either consumer-grade has been hacked to last longer and be more potent, or military-grade has been harvested from another sleeve and implanted. Both these forms tend to come with side effects, including headaches, disorientation and sensory overload. Depending on the reputation of the person making the modification though, attributes can be boosted for a modest sum. However, illegal neurachem (especially of the military variety) is no minor offense.

See Economy for relative costs of augmentations.

NEURACHEM TYPES

Reflexes Perception Speed
Smell Sight Coordination
Adrenaline Surge Numbing (useful to keep calm in stressful situations)

Drugs

There are dozens of street drugs and a few legal recreational substances as well. One drug that is commonly used is called Dwell. It produces a strong body high that can help stave off the symptoms of sleeve sickness and treat personality frag to a limited degree. It is not highly addictive, but those with frag can become reliant on it. It does have negative long-term effects. It's only approved for use for short periods of time after resleeving. It is illegal as a recreational substance.

NOTE: Merge9, a pheromone-based drug that allows for an empathic physical connection does not exist on our game.

Muscle Memory

This is not an augmentation. but rather is something that comes with a sleeve. Muscle memory cannot be artificially produced. If a sleeve has that, it requires the previous owner of the sleeve put that body through specialized training over a period of years. So a martial artist sleeve might innately block a blow or know how to do a kip up, but couldn't execute a perfect kata.

It's important to note that even if someone goes through intensive training to match the muscle memory and/or has appropriate neurachem and mod dumps, that person will never reach that sleeve's full potential. The only way they may come close is to spend years going through the training that the original sleeve owner did. The other way they may come close is say, a C-TAC soldier ended up in the sleeve of someone who went through the same C-TAC training. Even then, innate abilities of the sleeve's previous owner makes a difference in how effective in combat that person could be. The only ones who ever seemed to find a way around this are the Envoys, and the secret died with them.

In general then, combat muscle memory gives a person some combat ability, but does not make them a sudden badass if they weren't one before. The same can be said for other skills that require muscle memory, like playing an instrument or sewing. For someone in a new sleeve, it plays out sort of like discovering a hidden talent that provides a step up, but requires training to be used more fully.