Shadowkin

There exists a great many creatures in the world that are made entirely of shadow. These animals can dive into shadow as if it was water to take refuge from light, which will dispell them if they exposed to it for too long. Shadowkin are an extremely new phenomenon - only having come into existence during the later years of the Toxin Wars. No one knows exactly how these creatures to be, leading research from the Arcana department at Corvus University points towards them being a byproduct of the heightened ambient magic levels caused by the war. That many spells and amount toxicaster blood spilt left a great deal of residual mana that transmuted into the shadowkin, so goes the theory. One key piece of evidence for this theory is their appearence.
All the known types of shadowkin resemble small, bestial versions of the peoples of Garragunya - with the exception of the Blessed Triumvirate. The shadowkin lack any semblance of intelligence that their sentient counterparts possess, mere animals in the way they conduct themselves. Luckily for the world, these magical creatures have not affected the ecosystems of Garragunya in any real way. They exclusively prey on each other, or for those who we'd expect to be herbivorous who consume shadow. This has no lasting effect on the creature or plant they take the shadow from, as it will grow back in a few days.
When they first appeared around the grounds of Corvus University they reflected the people in the area, mostly Orru with a handful being phantoms of the other peoples in attendance. As the phenomena spread across Garragunya, the shadowkin created in an area would reflect the people who lived there. However once these magical shadows had spread over the whole of the world they began to diversify until all types were seen most everywhere, becoming a sort of shadow-ecosystem in the backdrop of life.
Whatever the circumstances that led to these shadows of the past come to be, they exist alongside us with little impact. Animals that specialize in consuming more magical prey have been witnessed preying upon shadowkin to no detriment, and the gods have not noticed them... or at least not purged them for violating the Bamal Yalgoo. And so these small patches of darkness merely remind us that life goes on, stained by war but still alive.