"A Periodica’s duty is to the people! Humanity comes first, and we are to ensure their safety." ― Platinum reciting the Periodica Motto on panel 094
Periodica are a species in Vindicaris. They are artificially created humans with elemental powers based on the Periodic Table. They are assigned to do different tasks such as escorting Systema employees to and from work. 
Periodica are physically the same as humans. All Periodica are created from a huge pool of mixed human DNA, so all are mixed race. They can occasionally have some non-human abnormalities, aside from colors. These include:
- Fangs/Shark teeth
- Pointed Ears
- Forked Tongues
- Slit Irises
- Sharper Nails
Bismuths typically have patterns in their irises to help differentiate them from humans, and may also get tattoos near their eyes to differentiate them further.
Each element has its own unique color that shows up naturally on a Periodica's body. At least one or more of the following is this color:
- Hair (part of hair)
- Tongues (always their color)
- Scars (typically older ones)
The parts of a Periodica that aren't their color are either black or white. Periodica with black sclera are always Radioactive, with very few exceptions. In addition, Radioactive Periodica also have pulsing patterns within their color.
Periodica blood is not the same color as their elemental one, however, and is instead a color pinker than human blood. 
Barcode and Tracking Chips
All Periodica are implanted with a tracking chip, and tattooed with a unique ba code over the chip. Barcodes are used for identification and as keys to access certain areas. Only high-ranking employees (such as Silver or the Dormitory Police) can access maps with tracking chip locations.
Education and Training
Periodica take mandatory classes from ages 4-18. Education from ages 4-14 is mostly human-like schooling, where they learn about science, math, history, languages. They also take classes on with information about Periodica powers, but without hands-on training.
At age 15, Periodica learn how to use their powers through hands-on training. Mandatory training ends at age 18, however many Periodica will continue training in their own time to stay in shape. At age 30, Periodica "Graduate" meaning they are moved abroad on for permanent work.
Periodica live in the Nursery until age 15, when they are moved to the Dormitory facility. They share dorm rooms until they’re 18, then they’re moved to their own individual rooms. Periodica can decorate their dorm rooms with temporary things like posters and potted plants. They’re not allowed to paint their rooms or damage anything.
All Periodica are made in test tubes and are sterile, so they have no biological relatives. They will still form familial bonds with each other, referring to each other as siblings or cousins.  Other types of relationships work the same as human ones.
It's common for Periodica to wear clothing that matches their elemental color. Outfit styles range from sci-fi battle suits to pajamas. The most common types of outfits are skin-tight suits with jackets. The Systema facilities have mall-like shopping areas where they can buy new clothes and armor.
All Periodica have their own Profiles in the SystemaNet database. They are used by Systema staff to keep track of basic personal information. These are different from medical records, which are much more detailed.
While Systema is continuously creating new Periodica, not all elements are in production. Some elements are too dangerous or expensive to mass produce. Hydrones are the most commonly produced because they're just robots. Accidents will happen during the production process, so certain elements may be created unintentionally.
Powers and Abilities
Regeneration and Death
Periodica can heal injuries much quicker than humans. Periodica can regenerate/heal injuries much quicker than humans. The exact time can vary from a several weeks to a few minutes depending on the element and severity of the injury. Only the fastest-regenerating Periodica can heal severed limbs, but the limb must still be intact.
If a Periodica doesn't begin healing their injuries immediately, they can suffer from long-term damage. Periodica can still die from many of the same causes humans do, such as illness or extreme injuries.