Warfare and economy with a widespread magic system where each person can create a semi sentient clone of themselves
I'm trying to form a world around a magic system that involves someone creating a shadow clone of themselves. Said clone can be willingly given away to another, but with some high risk.
To elaborate: Those Shadows appear as mute copies of their owner. They are made out of an entirely black material whose composition is somewhat like semi-solid smoke. They have mass, but can't exactly be killed by physical trauma, at most they'd only be scattered— after which they'd reform within a few seconds.
Another aspect of Shadows are Brands. A Brand is a coin sized, spiraling birth mark that can be moved around a person's body (Most have it on their Right Wrist. It is used to track the shadow's use time by how much of it is visible.
Now, there's a few more rules to this system:
* Everyone is born with a Shadow, and a Brand.
* Someone can split their shadow from themselves at will, the shadow can also be re-absorbed at any time through physical contact with the owner. If the shadow is not re-absorbed within 24 hours, the owner dies and the shadow disappears.
* A Shadow's use time can be recharged in real time to a maximum of 24 hours while within their user. (One second within the user counts as one second recharged.)
* Shadows have the same strength, dexterity and skill in crafts as their owner, but do not tire.
* The owner fully controls their shadow mentally when near it. It can perform any physical task the user would be able to.
* The user and shadow DO NOT share senses. 227
Instead the shadow is controlled by a combination of the user's unconscious mind, knowledge, and intent. They are otherwise mindless.
* If given a vocal command or instructions, the shadow can act them out from afar.
Now, something that adds a layer of complication is the possibility of Shadows being able to be willingly given to another person.
* When an owner is willing, a Brand (or multiple) may be passed form one person to another through skin contact after an agreement is spoken.
* The new owner can control the Shadow normally as well as keep it within them to recharge.
* The shadow keeps the original owner's physical capabilities and skill. Some semblance of the original user's personality remains in the Shadows, but it only surfaces in extreme situations. (For example, making a shadow kill its owner or one of their family could cause it distress to the point of it being unresponsive until the order is withdrawn. This of course varies from person to person.)
* If a shadow remains outside of its new owner for a full 24 hours, the original owner dies and the shadow disappears.
* If the original owner of a shadow is killed while their Brand is owned by another person, their Shadow will remain on the new owner— but be unable to recharge, disappearing along with its brand once the remaining use time it has runs out.
* If someone has multiple shadows, they can recharge them simultaneously, but each one's use time is independent of the other.
* When someone dies while having another's shadow, all shadows they hold disappear with them.
So far I can think of a few implications to this.
For one, more ambitious architectural/labor intensive projects could be accomplished by smaller populations. Shadows effectively double the labor able to be completed without requiring any additional supplies.
I'm thinking Kings or aristocracy could impose taxes on or receive Shadows as payments from their subjects. Armies would effectively be doubled in size, and a single man could control entire garrisons from afar by being given their soldier's Shadows before the battle. Sure, shadows can't be killed, but they can certainly be blocked, or punched through in order to protect or reach the ones controlling them.
And oh boy, when the shadows of the dead come into play things get even more interesting. Especially talented artisans' shadows may be kept as relics, soldiers may hand over their shadows before battle so that they can be used even after their death, resulting on stockpiles of dead shadows growing over the years.
Massive battles could be fought by the shadows of the dead, constrained by the 24 hour limit and forcing their commanders to make strategic decisions on how many they use and for how long!
But yeah, those are some ideas, I'd love to hear any others.
What sort of warfare techniques and economical practices could arise from such a system? 164