Periodica are a species in Vindicaris. They are artificially created humans with elemental powers based on the Periodic Table. According to Ces, Periodica are bred to work as slaves or sold off to the government, or whatever else Systema wants to do with them.
All Periodica have some sort of regenerative ability, though the effectiveness of it varies depending on the elements group in the periodic table. It is known that, while gases can regenerate entire limbs, nonmetals and metals cannot, however the Periodica must start to regenerate as soon as possible, else it may fail. It is currently unknown the regenerative capabilities of Alkali Metals, Alkaline Earth Metals, Metalloids, Transition Metals, Halogens, Lanthanides and Actinides.
All Periodica inherit a similar suite of abilities based on their element, however the level of skill between any two of the same element may vary drastically.