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# System prepended metadata

title: Synthetic Species Design Document

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# Synthetic Species Design Document

## Purpose

Citadel has long lacked a real synthetic race on main, due to balance concerns. This has resulted in every species including IPCs to just be "reskinned humans". While that's nice for balance standardizations, the precedents set by a previous era of the server/maintainer team shouldn't hold us back forever.

Thus, a base "synthetic" species should be created in code to standardize the basic balance/gameplay system for synthetic races. All synthetic races including IPCs, synthlizards, standard synths (base race, will just look entirely like humans but have these mechancs in them), and potentially proteans.


## Breakdown of mechanics

### Nutrition/Food

Food for synthetic species will be replaced by charge, via something akin to RP's system where they are able to recharge from one time "emergency batteries", cyborg chargers, or potentially via APC.
They should still be able to eat food, but have an awful metabolization efficiency so they would need much more to keep fed than standard recharges. (Unpreferred but may need to be done until cyborg rechargers are mapped in universally or near universally)
Synthetics for obvious reasons should not be able to get fat or "overeat" (unless someone wants to implement ethereal-like systems to make that a thing).
- Artificial fullness limit to prevent them from literally eating everything since they can't get fat.

### Chemicals

Optimally, they would not allow chemical injection at all, but unfortunately some effects (see: cult conversion, similar) require chemical intervention to resolve (synthetic specific things aren't out of the question but aren't going to be a thing for a long time), so it is currently infeasible.
They should however be completely immune to the vast majority of bloodstream effects of healing and poisonous chemicals, same for any touch/vapor effect from organic healing/poison chemicals.

### Mood Systemw
Synthetics should be entirely immune from the mood system, with all mood events (like hunger, for one) being deemed important/crucial enough just being given their own static effects for if someone has mood off.
Hunger, in specific, should apply the bog standard slowdown to them.

### HEALTH SYSTEM (Experimental)
Detachment from the standard 100 to -100 full health crit death system:
Only bruising/burns would count for damage and only in certain areas like chest/head
Everything else would serve to disable them. They will be more vulnerable to disabling effects like limb disable from damage/random dropping items from "broken" arms/wounding than outright death through damage addition, other than through chest/head.

This is something I want to do for all humanoids/etc but at the moment this makes most sense for synthetic testing.

### Damage

#### Bruising, burns

Synthetics will have their bruising/burns healed with welding/cable coils respectively, however:
If they get damaged past a certain extent, they will need a surgical procedure to repair it. They will be able to self repair past that extent to that extent (maybe around 20-30 damage per limb) but will be unable to heal past that threshold (so they'd keep the "top" portion of damage) without surgery.
Maybe they will be able to "self surgery" with an extremely time intensive process but for the most part after that damage threshold they will require others to help restore them to full.

#### Clone
Not applicable to synths
There's like nothing that does this that we care about
Maybe make decloners have a mild EMP effect from the "radiation"
and slimes can just knock them down on contact or something from the electrical shock

#### Radiation
Most radiation effects don't make sense BUT I do not want to make them immmune to them
At high radiation it should have the effect of doing scaling-capped system instability as well as their own effects (fluffed as radiation disrupting electronics)

#### Toxins - System Instability
See "Health System" - Does not contribute to death through damage addition, has own threshold for death (200 or so)
At higher instabilities they will start to encounter glitches, like being randomly knocked down, item dropping, lower melee damage, muscle spasms when attempting to act, slower speed, culminating in a full non-unconscious stun to death.

Taken from sources like EMPs, potentially shocks and other things, disrupting nanite programs etc etc.
Rather slowly regenerated outside of a charger, quickly regenerated in a cyborg charger.

#### Oxygen deprivation
They wouldn't breathe, but refer to "Pressure" section
They'd require gas capable of cooling them and would emit heat. Maybe literally because atmos is good now? Who knows!
~~Alternatively we can bandaid them to breathe normally if this is deemed OP~~
Obviously they won't have any positive effects from any gases etiher.

#### Wounding
- Should have a separate class of wounds for synthetics, but otherwise be in full effect
- Synthetic wound repair surgeries/methods
- They will have more varied wounds and get wounded easier than organics, but in exchange, their limb damages won't count to total health/death and for the most part wounds will not affect anything outside of that limb.

#### ~~Bleeding~~ Coolant has been decided on
- Not applicable, they have no blood
- Yeah, they have no blood.

#### ALTERNATIVE: COOLANT
- Blood but they don't straight up start dying without it, instead suffering from increased vulnerability/impairment
- Specific hashes exist so they're equivalent to blood for forensics
- **Overall**, coolant should be rather important for them, and definitely lead to them dying where they would otherwise live if they do not manage it well enough/lose too much of it, but shouldn't **alone** result in death if they run out. See heat, cold, pressure.
- Maybe have it reduce instability faster when high and have instability slowly drain this?

#### Heat, Cold
- Should have a far higher tolerance for temperatures than organics
- Beyond said higher tolerances, should take damage faster than organics (think: working, or failing rapidly).

#### Pressure
- Slightly higher tolerances for pressure.
- Potentially a better system for handling vaccums involving synthetics needing "cooling" to work a la how baystation does it, and the pressure isn't what kills rather than the lack of air for cooling.
- **After discussion**: *:  It's already been established free spacewalking would be really dumb. Instead, we can do a system based on coolant/suit/suit coolers. Without sufficient cooling they'll boil off coolant (SEE HEAT, COLD OTHERWISE), and at a certain point they won't have enough and start to burn. How this'll tie into suits/coolers is, coolers will be **required** for them to operate in low pressure to not burn to death, and suits will make said coolers take less energy to run as they create a closed system. Efficiency will also be based on coolant.
    - Alternatively just hardsuit check because >new item
    - But that's lazy so we'll see if it goes this way

### Genetics
Genetics is not applicable to them due to them having no DNA

### Revival
For the first patch cloning/etc will likely be allowed due to the difficulty of recoding this, same for defibbing
Optimally, they'll have a different robotics-based revival method potentially involving printing a new body and transplanting their brain in
~~Hardcore species without clone backups because their brains aren't organic haha just kidding unless?~~

#### Brain
Refluffed positronic brain.
In the future we may look into being able to construct crewmembers via frames and real posibrains but the balance implications of that are too awful to look at right now, so instead we're just respriting and renaming a brain to be a posi for them.

### Limbs

Their limbs would be a new kind of limb with bodypart robotic without inherently having a different icon base than normal limbs. This would ofcourse be different for subspecies as necessary.

### EMPs

EMPs should never hardstun synthetic races, rather instead inflicting Toxins (system instability), and potential disruption effects like forcing combat mode off, slowing down, and doing a small amount of damage in the meantime.

### Surgeries

Surgery procedures should be tied to the new BODYPART_STATUS added for synthetic limbs, and the bare minimum would be custom surgeries for repair (more above), organ manipulation, similar.
Surgeries should be aimed to be done in robotics rather than medbay, but unlike normal surgery, would use more mechanical (think welder/coils/screwdriver/crowbar/etc) tools than actual surgical tools, as well as some of them **potentially** being able to be self-performed with the right setup (and at a very low efficiency compared to someone helping you)

### Nanites, viruses

Tentatively, they should be fully immune from viruses without inorganic biology, and nanites should only have synthetic effects work on them.
Was going to say full immunity but locking them out of two double edged sword systems is silly.

### Misc balancing
- Synthetics should take less damage from shocks but take more disorientation/incapacitation effects from them. Think more stamina damage, hard-knockdowns, combat-lockouts for a duration of time due to shocks.


### Misc notes from feedback
- Might help to make them have some sort of expansion capability lateround since they can't power-creep as hard as normal humans due to their immunities
    - Cybernetics not taking much work to install + not hardstunning on EMP? Different effects?
- Probably make synthflesh still somewhat work on them just really awfully even if it doesn't make lots of sense
- Totally pressure immune + cooling requirement?? OP??
- More things to make them sidegrade vs upgrade/downgrade?
- self limb attach after forceful sever? Maybe? OP??
