Feruchemist

You are invested with power and are a Feruchemist, able to store certain traits in specific alloys to draw on them another time.

Feruchemy is an end-neutral manifestation of Investiture that allows the user to convert certain attributes into Investiture and store them in metal that they are in physical contact with, and to later retrieve them from the metal. As an end-neutral art, Investiture is not gained from an outside source (as it is in end-positive arts) and Investiture is not permanently lost (as it is in end-negative arts). Ordinarily, when a Feruchemist is tapping an attribute at the same rate it was stored, they are able to get out exactly what they put in, for example, if they store 50% of their strength for one hour they can tap that and be at 150% of their strength for one hour. However, if the Feruchemist taps at a greater rate, then some of the attribute is lost, to facilitate the compression of the Investiture. This means that a Feruchemist who stores 50% of their strength for one hour might only be able to stay at 200% for 25 minutes, rather than a full half-hour. The more a Feruchemist compresses the attribute, the more is lost. While a Feruchemist can only store attributes at a reasonable rate, there isn't an upper limit of how much they are able to tap at any given time.

The type of metal determines what attribute can be stored within it. Pieces of metal that have been charged by Feruchemists are referred to as metalminds in general, or more specifically as the type of metal with an added "-mind" suffix. The act of charging, or Investing, a metalmind is referred to as storing and the act of retrieving the stored attribute is referred to as tapping.

A larger piece of metal will be able to store more of an attribute, but the scaling is not linear; there are certain thresholds of size where the amount of attribute that can be stored increases. If a metalmind is broken, the stored attribute will be split among the pieces. This is because the power inside the metal acts like a gas acts inside a jar. It is possible to store and tap using molten metal (setting aside the conventional hazards of touching molten metal) which would have some effect on the stored Investiture. If the molten metal is mixed to form an alloy, however, the Investiture will become inaccessible, even if the alloy in question is Feruchemically viable. If the alloy is Feruchemically viable, a Feruchemist will not be able to store as much of an attribute as they could in an identically-sized metalmind: while the original Investiture is inaccessible, it does still take up "space" in the metalmind.

Ordinarily, a Feruchemist's stores are keyed to their Identity and are inaccessible to another Feruchemist. However, other Feruchemists can sense the presence of the original Feruchemist's stores.

In order to get the most storage out of a metalmind of an alloy, the metal has to be alloyed in a specific combination of metals. If the metal does not have the right mixture, it is considered impure. This is likened to how Allomancers require these 'pure' metals as well. If a metalmind is not pure, it will not hold as much charge as one that is alloyed correctly with the same size

 

Metalminds

You have 16 metalminds on your person, taking the form of composite bracers made to wear on your upper arms, and you use them to store your abilities when touching them. You have one made of each of the sixteen metals, (Iron, Steel, Tin, Pewter(91% tin, 9% lead), Zinc, Brass, Copper, Bronze, Chromium, Nicrosil(Nickle, Chromium, silicon), Aluminum, Duralumin(96% aluminum, 4% copper), Cadmium, Bendalloy (Cadmium & Bismuth), Gold, Electrum(45% gold, 55% silver)) and you can store them, though it is considered safer to wear them. You have to type them into "Other possessions". As long as you are wearing them, they cannot be taken forcefully from you. You can use other objects of the metals to store power(including earrings), as long as they have the proper composition and you are touching them. The bracers can store up to 168 hours of each trait, and other metals can store one hour of trait for every fourteen grams of metal.(2 hours per ounce).

Physical Traits

You have learnt to store four physical traits in your metalminds, the ones shown below.

Iron: Stores physical weight, you weigh less while storing, you weigh more while tapping, though your body does not change or become denser. Also, when tapping, your body is reinforced so that you are not damaged by your weight bearing down on you. You cannot store more weight at a time than your actual weight, and while storing weight it becomes progressively harder to move around accurately, loosing 10 feet of speed when you are storing full weight, but you gain speed equal to your dexterity modifier when storing. 

Iron is used to store physical mass. This is accomplished by changing the Skimmer's mass, not by changing the effect of gravity on the Skimmer. This change does not affect things that the Skimmer wears, but is great enough that a Skimmer storing weight can safely fall any distance, as the Skimmer's surface area is sufficient to slow the fall to safe speeds.
A Skimmer tapping iron can grow proportionally heavier than normal, and although this is not as useful as storing mass in many cases, it has significant martial applications. Specifically, by tapping iron during key moments, Skimmers can add force to their blows, and can use added weight to withstand attacks. It can be used to counter Coinshots or Lurchers, for example, by increasing weight when pushed, one can instead push the Coinshot back. Furthermore, the added mass from tapping an ironmind can wreak havoc with steelpushes/ironpulls if the Skimmer is being used as the anchor.
Tapping iron grants the Skimmer the strength requisite to remain standing, including a partial increase in the density of their body, but this increase in density is limited and does not, for example, affect the Skimmer's vulnerability to penetration.
The law of conservation of momentum still exists when using iron Feruchemy, so while tapping weight doesn't significantly increase the speed of falling (not considering air resistance), decreasing one's weight to half will double one's speed.

Steel: Stores Physical speed, while storing, you experience everything at an increased pace, essentially living less, and while tapping you live at a decreased pace, everything else seems slower in relation to you rather than you seeming to go faster than everything else. When storing, your speed reduces to at most 1 foot, and when you tap you can use the speed stored and add it to your actual speed for one turn, burning that which you use You are not able to use speed to go faster than Mach 2. In battle situations, you get two turns when tapping speed.

Steel is used to store physical speed. Then, by tapping their steelmind, a Steelrunner can move many times faster than a normal human, even one burning pewter with duralumin, as well as burn metals faster. While storing speed, a Steelrunner is very sluggish and is described to feel like moving through molasses. Sazed, a notable Feruchemist, regards steelminds as one of the most difficult minds to fill. Steelrunners can withstand the Gs they are put through, but they can't ignore wind resistance and friction and will burn up if they start running too quickly. This can be overcome with Edgedancers' abilities.

Tin: Stores the senses, so you can spend time with decreased eyesight to have increased eyesight at a later time. Each tinmind can only store the sensitivity of one sense, the sixteen metalminds you have are built with the storing of the 5 basic senses in mind, if you want to store more senses you must have other bits of tin to store them in blindsight and truthsight can be stored, as well as darkvision.

Tin is used to store sensitivity of senses. One sense may be stored each in a tinmind. Unlike an Allomancer burning tin, it does not allow a Windwhisperer to see things that would be otherwise unobservable; instead, it compounds the potency of their senses currently available. While storing senses, those senses become weaker. For example, Sazed wore glasses while storing eyesight.
Tapping sight causes the edge of the Windwhisperer's vision to blur, and sacrifices immediate field of vision in favor of a more distant, binocular view. Tapping too much sight can induce nausea. Storing sense of smell dilutes a Windwhisperer's sense of taste.
It is possible for a Windwhisperer to store more than the five traditional senses in a tinmind. An example of this would be the the ability to feel pain.
Creatures with other senses can create tinminds for those senses as well as the standard five. For instance, a platypus Feruchemist could create an electric field sense tinmind.

Pewter: Stores Physical strength, while storing it you become less muscular, your muscles seem to deflate, and when tapping it you become more muscular, possible destroying your clothes as you expand, though you never grow more than one size. You can never store so much muscle that you die.

Pewter is used to store physical strength However, as opposed to the simply enhanced body granted to an Allomancer burning pewter, a Brute tapping a pewtermind gains muscle mass and becomes physically larger. The additional muscles allow the Brute to have increased strength. For this reason, pewter metalminds are often designed to be able to stretch wider to accommodate the extra muscles. While storing physical strength, a Brute becomes scrawny and weak.

It's possible for a Brute to tap so much strength that their girth makes it difficult for them to maneuver properly.

Cognitive Traits

You have learnt to store the four cognitive traits, shown below.

Zinc: Stores mental speed, when you are storing you have disadvantage on all intelligence checks, and you have a reduction in intelligence score equal to how much mental speed you are storing. When tapping, you have advantage on all intelligence checks, and gain intelligence score equal to however much you are tapping.

Zinc is used to store mental speed. It allows the Sparker to think very quickly and come to conclusions faster. While filling a zincmind, the Sparker will be dull-witted and slow. Storing does not affect the Sparker's ability to take in physical information, but it does increase the time it takes to process that information. For example, a Sparker filling their zincmind will perceive words without delay, but will take longer to parse their meaning. Tapping zinc has the odd side effect of making the user hungry.

Brass: Stores warmth (no clue how this is cognitive). When storing, you become colder and have resistance to cold damage, though your body will not let you store so much heat at once that you freeze or take cold damage (from storing, environment still effects you). When storing you are immune to heat/fire damage. When tapping, you become warmer and have resistance to heat damage, though you never become warm enough due to tapping to take heat damage(other sources can give you heat damage, though). When tapping, you are immune to Cold damage.

Brass is used to store warmth. While filling a brassmind, a Firesoul will be cool. A Firesoul's body, not unlike a Skimmer's, is able to resist the higher temperatures of their Feruchemy, but are not immune to intense heat in general. By cooling the body by filling a brassmind, however, one could resist higher temperatures; heat would flow to the colder region of their body and then get stored in the brassmind, allowing one to become immune to fire and other sources of intense heat by carefully regulating the rate at which one filled their metalmind.

Copper: Stores memories. You can store a memory in copper, forgetting it, but as long as it remains in the copper it is unchanged from when you put it in there. When you pull it out, it begins to degrade like a normal memory.

Copper is used to store memories. Since the memories in a coppermind do not degrade with time (although they are vulnerable to any god who can sense them manipulation while being transferred), it is perfect for the collection of enormous quantities of facts. For this reason, Feruchemists were much more likely to be scholars than warriors. When an Archivist stores a memory in a coppermind, it immediately disappears from their memory. Memories stored in a coppermind are filed individually and are not seen as one whole memory to the Archivist. The best users of copperminds would create indexes to find memories much faster. Finally, the longer a memory sits outside of a coppermind, the more it degrades, though this is due to the brain's own imperfections, not any quirk of the magic. Keepers undergo extensive training in memory retention to make the most of this ability. Copperminds can not store muscle memory, only mental memory.

 Bronze: Stores wakefulness. When storing, you become drowsy and can fall asleep, storing the maximum amount of wakefulness (You do not gain rest benefits from storing wakefulness). You have disadvantage on inspiration and perception when storing. When Tapping, you become more awake and alert, gaining advantage on perception and inspiration.

Bronze is used to store wakefulness. It allows the Sentry to stay awake for extended periods of time, or to heighten awareness. A Sentry filling a bronzemind becomes drowsy. It is the only type of metalmind a Feruchemist can store into while sleeping. Caffeine can be used to generate extra wakefulness, but it would feel different upon being tapped.

Hybrid traits

You have learnt to store the four traits that are called the Hybrid traits, shown below.

Cadmium: Stores breath. While storing, you need to hyperventilate to get enough oxygen to survive, and while tapping you need to breath less, up to not needing to breath for a time.

Cadmium is used to store breath. While storing breath, the Gasper must hyperventilate to keep their body oxygenated. Tapping a cadmiummind allows the user to go without breathing, or to introduce extra oxygen into their bloodstream.

Bendalloy: Stores energy, or more specifically, nutrition and calories. When storing, you can eat and not be full, and drink fluids and not be satisfied. You do not gain weight from the food, as all parts of it useful to your body that your body would store are put into a bendalloymind. A bendalloymind can only store food or fluid, and your metalminds are built with this in mind(2 different sections). When tapping the Bendalloymind, you can go for long periods without food or drink.

Bendalloy is used to store nutrition and calories. While filling a bendalloymind, a Subsumer is able to eat large quantities of food without becoming full. Tapping such a metalmind will allow the user to go without food. A separate bendalloymind can be used to store fluid intake.

Gold: Stores Health. While storing it, you body becomes less able to fight off infection and diseases and less able to repair itself. For every two hours of health you store, you can recover one hit point by tapping for two hours. When tapping, you heal yourself from the effects of all poisons and toxins and wounds

A goldmind can be tapped to both heal at an accelerated rate or to heal from wounds that would normally be fatal. It is hard to fill a goldmind, due to the fact that it requires the Bloodmaker to spend time sickly and weak. Gold does not heal diseases as efficiently as it heals wounds.
Gold healing works by aligning an individual's Physical aspect to their ideal self as recorded in their Spiritual aspect. This does not prevent them from aging or certain genetic diseases as those are considered part of the ideal.
Aluminum in a wound will make it impossible for the Bloodmaker to heal the injury around the metal for as long as it remains in the body.
Gold healing would interact with organ transplants in an interesting way. This can be either beneficial or detrimental depending on the circumstances. Bloodmakers' bones are particularly interesting due to the time they spend weak and sick, which creates distinctive oddities in the joints and bones.
Damage to the soul, such as that caused by Hemalurgy, can be healed by Bloodmakers, though it would take a lot of health to regain the stolen ability. A Bloodmaker would also be able to heal a wound from a Shardblade, or being withered by a shade.

Electrum: Stores Determination. Electrum is used to store determination. A when filling an electrummind you will become depressed, having disadvantage against any ability checks regarding mental fortitude. You can tap it later to enter a manic state where you are incredibly determined and hyper focused, gaining advantage on ability checks and saving throws regarding your will. 

Spiritual Traits

You have learnt to store the four Spiritual traits, shown below.

Chromium: Stores fortune. When filling a chromiummind, you become unlucky, having disadvantage on any roll you do while filling it. When tapping, you gain advantage on any roll you make for the duration. You can use three hours duration at once to guarantee a success on any roll. Also while tapping, events and coincidences that are to your benefit happen more often, and vice versa when filling.(within reason, it mostly does not effect happenings far away from you or that will not affect you regardless of the outcome.)

Nicrosil: Stores investiture. This ability is not well understood (even by those who utilize it). A Soulbearer storing Investiture stores their ability to use their Investiture. Therefore, a Soulbearer could store their ability to use Feruchemy and another person tapping it would be turned into a temporary Feruchemist who has the ability to fill a metalmind (assuming the nicrosilmind was unkeyed). Among other things, a nicrosilmind can be used to store the divine Breath of the Returned and the ability to use various surges of the Knights Radiant. Filling a nicrosilmind as fast as possible hides a person from an Awakener's life sense. This is primarily used for creating unkeyed metalminds for others. (see Unkeyed/Unidentified Metalmind)

Aluminum: Stores Identity. When you store, you lose your sense of self and all alignment, and when you tap, you have an enhanced sense of self, knowing more truly what and who you are. while tapping, you are resistant to magical charisma, and attempts to shape-change you.

Aluminum is used to store "spiritual sense of Identity." This ability is not fully understood. A Trueself who fills an aluminummind to the point where they have no Identity and then fills another metalmind is able to produce a metalmind that any Feruchemist with the relevant power can tap.(see Unkeyed/Unidentified Metalmind) A Feruchemist can tap another person's metalminds by filling their own aluminummind completely. Trueselfs can heal damage done to them in the Cognitive Realm by storing Identity, but it takes a roundabout method. Storing Identity makes the Feruchemist more susceptible to many things, such as Forgery. It is unclear why Identity can be stored in and withdrawn from an aluminummind when other Invested Arts cannot affect aluminum.

Duralumin: Stores Connection. When storing, others have lessened awareness and friendship with you, and you have trouble making connections with others. When tapping it, you can make connections easier, and any creature within 50 feet is charmed. When tapping you also know innately the main language of the land you are in, though you have an accent from your home.

Filling a duraluminmind can be used to reduce other people's awareness of and friendship with the Connector, as these Spiritual Connections become stored away. Tapping it would strengthen Connections or allow the Connector to form relationships faster.
Southern Scadrians use unsealed duraluminminds to enable them to communicate with others on foreign lands. They still retain their native accent when doing so, though someone could develop a local accent by blanking their Identity. This ability can be used on other planets, though it does not grant the ability to travel between worlds.

Unkeyed/Unidentified Metalminds.

Through use of Identity and Investiture storing you gain the ability to create Unkeyed and Unidentified Metalminds.

As an action, for one long rest, you can store Identity as fast as you can(making it so that you have no identity, essentially) and then another trait, creating an unidentified Metalmind with 4 hours worth of any storable talent that anyone who has the ability to draw from metalminds of that specific type(i.e. gold for healing) can draw on, but you and others can only store unidentified traits within the metalmind.

You can, instead, store Investiture while storing Identity, creating an Unkeyed Metalmind that anyone can draw on to give them any one Feruchemical capability as long as they are drawing on the blank investiture.