Possessing a shadow

[Noxangelo]

Is it Possible for something to possess, replace or otherwise manipulate your shadow.

My reasoning behind this being possible is that unlike our world, shadow is a fundamental part of the universe. I believe some shadowcasters fluff text has them pulling power and shadowstuff out of their own shadow.

What do you guys think?

Or am i late too the party and these things are common fare?

[Tzardok]

I don't remember wether there are spells that allow something like that, but propably. The shadowcaster's mysteries do this fluffwise, but I don't think there are any canonical that do this; but the shadowcaster feat Shadow Cast allows you to designate a adjacent square, and as long as that field isn't threatened, your mysteries don't provoke AoO. The idea is that the shadow casts for you.

If we enter homebrew, we've got more. Amongst the mysteries and feats added in Project: Descent of Shadows (https://forums.giantitp.com/showthread.php?74519-Descent-of-Shadows-Project-Shadow-Returns) there are a bunch that do more with the shadow than just adding fluff. Also, I once made an alternate classfeature for the sha'ir that uses shadowcasting and animates your own shadow to serve as your familiar. It's found here. (https://forums.giantitp.com/showsinglepost.php?p=24749335&postcount=116)

[Paragon]

There is the Shadow Well spell I have used once. Flavor full and fun :D

[Gruftzwerg]

Shadow Double (Assassin 1, Hexblade 2, Sorcerer 2, Wizard 2)
from Drow of the Underdark

Creates a shadow double of you. It can attack to deal 1 point of STR damage every time it hits.

[Psyren]

You could fluff Greater Possession this way since your body vanishes. Just say you climb into their shadow.

[CIDE]

Umbral Spy Pg155 from Forge of War (Eberron). It's an incorporeal man-made construct but it has the ability to jump into people's shadows for thee purpose of collecting information.

[SangoProduction]

Yes, there are numerous spells that manipulate the shadow (yours or "plane of shadow") in one way or another. Even outside of Spheres of Power. But SoP does have better concentration of them in the Dark sphere. Because... it's about darkness. And shadows are... Anyway.
The Wraith spheres class can possess elementals from nonmagical matter by baseline. Really wouldn't be too hard to refluff that to literally possess a person's shadow. I could easily see justifcation for each of the 4 base elemental forms.

[Noxangelo]

Yay, lots of cool stuff.

that umbral spy is cool, i wonder if you give it spell-like abilities, can it cast them while bonded.