Of the total population on korodel, roughly 1% of it is lucky or unfortunate enough to be a Casters. Casting is a genetic art, passed down from parent to child, often keeping their metal types uniform along the blood lines. Similar to Linking, Casting comes into two main types. Pure Casting, giving the user the ability to manipulate a single pure metal and it's return type and Alloy Casting, allowing it's user to manipulate a specific alloy, it's pure metal components and their return types. Alloy Casters also get a special return type substance, which comes from converting their alloy specifically.

The mechanics of early Casting can be found in the mastery Casting: Control

It is incredibly rare for a Caster to naturally develop their abilities. For most individuals with this manifestation they must go through an awakening to first activate their power. Nicknamed “snapping” the awakening is usually triggered by some form of traumatic event in which the Casters life feels threatened.

A common way this is done is through the use of crowns. Casting is incompatible with Crowning as the two manifestations conflict, the effects of which can be devastating to a Caster. In attempting to Crown as an unawakened Caster, the user will first experience intense nightmares which quickly progress into severe hallucinations and inevitably madness. If the user is allowed to continue past this point, it's very likely the results could lead to death.

If done right however, in a controlled environment, it is a quick way to awaken someones Casting potential.

Though each Caster is strictly confined to their return types, each individual will have their own variant of the substance they produce. This is known as a “Birth Type” and varies from person to person. For example: a Cobalt Caster will always produce wood as a return type, but where one Caster may produce mahogany another may produce birch.

Birth types are usually a result of environmental factors or circumstances surround a Casters upbringing before they first awaken.

Currently, Casting is the only art confirmed to travel through a bloodline. As such it is also one of the few arts to have genetic factors play a part in it's development.

If a child is born from a Pure Caster and an Alloy Caster, things get a little more complicated:

If both the Pure Caster and the Alloy Caster share a metal type: there is a 50% chance of the child becoming a Pure Caster of that metal type. Alternatively, there is a 25% chance of the child becoming a Pure Caster, talking the Alloy casting parents other metal as their primary Metal type and finally, a 25% chance of the child becoming an Alloy Caster of their parents Alloy Type.

If the Pure Caster and the Alloy Caster do not share any metal types: The child has a 75% chance of becoming a Pure Caster, taking one of their parents pure metals as their Metal Type. Alternatively there is a 25% chance of the child becoming an Alloy Caster, sharing the Alloy type of their parent.

Across both of these scenarios, similar to the rare effect occasionally seen in Pure Casters, if both parents share a compatible metal there is the very slim chance that the child will become a Alloy caster of a different type. This is yet to be documented but can in theory happen in a union between two Alloy Casters or a Pure Caster and an Alloy Caster.

An example of this effect would be in a union between a Iron Caster and Inconel Caster. The child would inherit the Iron from one parent and the Nickle from the other, resulting in a Invar Caster being produced.

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