I originally posted this in my Facebook group over two years ago, but here's a slightly updated version on a page from the Sentinels' training manual. Topic: vampires.
Both subspecies.
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DAYERS
The first Dayers were Gifted humans who had turned into Nighters, but managed to preserve or eventually regain their rationality and decided to fight with the humans and shifters against the Nighters in The First Great War.
At that time, they still kept the Nighters abilities and appearance, as well as their bloodlust, but refused to harm humans and shifters and therefore fed on animals and other Nighters.
As a sign of gratitude, after the war was over, the Great Spirits of Nature gave them back their human appearance, lessened their thirst for blood and made it possible for them to have children. After that transformation, the terms Dayer and Nighter were created to distinguish between the human-like, in control of their thirst vampires, and the cursed, bloodthirsty vampires, whose habits are mostly nocturnal.
NIGHTERS
The First Nighter (also known as The Unnamed King as his name was erased from historic records) was a greedy human who challenged the Great Spirits of Nature (according to some religious beliefs - the Angels) and who was cursed by them to live forever in a mutated body with a never-ending thirst for blood. He later escaped the cave he was held captive in and created more Nighters by killing humans and then reviving them with his blood. He used his newly-created army of Nighters to attack the humans in what is now known as The First Great War.
DAYERS
Dayers look like humans and their appearance varies, but most of them are slim and with pale skin.
NIGHTERS
Nighters are extremely slender, with bones poking under the skin, resembling a skeleton covered with deceptively thin grayish skin that looks like a scaled membrane. On a postmortem examination, it was discovered that the scales were only deep wrinkles in the skin and that the skin is actually very elastic and endurable.
DAYERS
Hair colors include the same as that of humans.
NIGHTERS
All hair falls off the body in a matter of weeks after the turning, but at first, a Nighter's hair color is the same as it was before the human was turned into a Nighter.
DAYERS
Like human's, but the average Dayer has better hearing than the average human (it is at about the same level as a shifter's when the shifter is in animal form).
NIGHTERS
Pointed. The hearing is better than that of a Dayer.
DAYERS
Same colors as those of humans, but they would sometimes be un unusual/rare shade.
NIGHTERS
A Nighter's iris color depends on the eye color of the person they were when they were alive. After a human becomes a Nighter, their eyes get a reddish/rusty hue. For example, light blue eyes might become dark violet. The white area around the iris may become red due to many enlarged blood vessels.
DAYERS
Retractable.
NIGHTERS
Whenever a Nighter is being hunted, they would have their fangs at full length, but postmortem examination showed us that they are retractable like those of Dayers. However, on average, a Nighter's fangs are longer than those of Dayers.
DAYERS
Dayers don't have claws.
NIGHTERS
Nighters' nails harden, curve and grow into claws of about 2 - 2.7 inches.
DAYERS
Human or shifter blood, plus human food. Drinking blood from other Dayers is not forbidden, but it is considered unconventional and unpractical as the Dayer who is being drunk from will need to feed to replenish his/her blood. Drinking from animals is considered gross, and there are no records of Dayers drinking from Nighters.
NIGHTERS
Victims to the Nighters' almost insatiable thirst are mostly humans, Dayers and shifters, but when such prey is not available, Nighters are known to suck the blood of animals and even other Nighters. However, we suspect Nighter blood to be the least nourishing.
DAYERS
Healthy Dayers need about 450 - 500 ml four or five times per year.
Sick, injured, pregnant or breastfeeding Dayers need to receive more frequent, but much smaller doses of blood until they are healthy/give birth/stop breastfeeding. The exact amount depends on several factors (including the state of health of the Dayer) and is determined by a doctor.
A couple of tablespoons of blood are given to babies daily and every other day to toddlers up to the age of three to help boost the immune system of the children.
NIGHTERS
As often as possible. Young/just created Nighters will drink even after having gulped enough to sustain themselves.
DAYERS
Dayers do not need to hunt. They can obtain blood from special facilities, or, when they can afford it, from private Feeders.
Feeders can be human or shifters (rare). Only mentally stable, healthy adults who were not pressured into becoming Feeders and have a signed feeding employment contract with a Dayer can legally be Feeders. One Feeder can serve one or more Dayers as long as all employers know that the person serves as a Feeder to others and the Feeder doesn't give away their blood more than four times a year.
Due to the hunting instincts preserved in some Dayers, the Feeders contract could include a clause, stating they agree to be "hunted" by a Dayer. Those types of "hunts" are a simulation and can be done only with a special permission by authorities which is given after both the "hunter" and the "hunted" undergo a psychiatric evaluation and it is determined the "hunted" isn't going to be in any real danger. If such a permit is authorized, the "hunts" can take place only in private areas, where no ordinary humans are allowed (with the exception of those who already know about the existence of supernatural beings). A neutral and authorized party called an Observer should be present during the hunt to make sure the Dayer doesn't get carried away.
NIGHTERS
Just created (a.k.a. newborn) Nighters will attack pretty much everything with a pulse or even the Nighter who created them. There's no stalking, no hiding, just an immediate attack of their prey.
Young Nighters are considered extremely irrational, but slightly more in control of their thirst and slightly less aggressive than newborn Nighters. They are more likely to stalk their prey, although they quickly lose patience.
Older, more experienced Nighters that have recovered part of their rationality will be more careful when stalking and overpowering their prey and are therefore more dangerous as they are less likely to attack out in the open and attract attention, unless, of course, they are starving.
DAYERS
Average Dayers are healthier than humans and heal faster than shifters, but not as fast as Nighters. Their recovery speeds up when they drink blood.
The Zakkay (a.k.a. Purest of the Pure) don't have anything but Dayer blood in their lineage. Very few of them are left, but they are immune to most human diseases, including cancer and STD-s.
The Octavians (a.k.a. Eighters) have nothing but Dayer blood for at least eight generations. They are slightly less immune than the Zakkay although there have been no recorded cases of them having cancer.
For information on hybrids with Dayer blood in them, please refer to Section IV - Hybrids of the Humans & Humanoid Species 101 manual.
NIGHTERS
Not much is known about the health of Nighters.
They don't die unless they are killed and they don't cull their prey, therefore, we can assume they are immune to all human diseases.
They heal much quicker than any other humanoid species as long as they are supplied with blood to drink.
For more on wounded Nighters and regeneration, refer to further chapters in this section.
DAYERS
Just as humans and shifters, a Dayer's rationality varies with each representative of the species.
Due to easily accessible drinkable blood, Dayers rarely suffer from "blood rage" - a condition which would cause them to act more irrationally than they normally would.
NIGHTERS
It takes an unknown amount of time for the Nighters to gain some control over their blood thirst and regain some portion of rationality. Many of them are executed by members of the Order of Sentinels or murdered by other Nighters before that time comes. Even "sentient" Nighters cannot be reasoned with as bloodthirst overcomes their sanity.
DAYERS
Dayers are healthier, stronger and faster than ordinary humans and sometimes even shifters.
Unlike Nighters, the sun doesn't bother them and they could stay outside during a bright day without any problems.
NIGHTERS
The average Nighter surpasses the average Dayer, shifter and human in strength, speed and agility. However, a well-trained Dayer, shifter or physically Gifted human may be able to catch up with a Nighter or (on rare occasions) even physically overpower a Nighter.
Another advantage the Nighters have is their health (refer to the information above).
DAYERS
Blood thirst is still present, although kept under control, except in cases of captivity and starvation, grave injury, unstable mentality or blatant disrespect for the laws of the supernatural world.
NIGHTERS
Bloodthirst is the driving force behind everything a Nighter does. It makes them irrational and extremely detrimental.
Nighters are sensitive toward bright light and have problems staying under the sun for extended periods of time.
DAYERS
Only through sexual intercourse.
NIGHTERS
The exact process is unknown, but it involves killing a human, then reviving them with the blood of a Nighter.
DAYERS
Dayers are compatible with other Dayers, humans and shifters.
NIGHTERS
None.
ABOUT DAYERS
People (more often humans than shifters) often describe Dayers as domineering and/or alluring, even if they can't explain why they feel that way.
ABOUT NIGHTERS
Hunt down with extreme caution.
Eliminate on sight.
Don't try to capture and interrogate; Nighters lose the ability to speak human languages.
IMPORTANT: Due to the violent, unrestrained and deadly nature of Nighters, collecting data on them is extremely rare and difficult. As a result, some of the data may not be exact.
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So, funny fact: I'd completely forgotten about the Zakkay and the Octavians as concepts. I'd meant to include those ideas in Alec's story, so good thing I revised this in time for that!
Anyway, what do you think of the Sentinels' manual?
Please give it a VOTE if you are a Sentinel in training and you've found this useful! Or if, you know, you just liked this extra.
As always: if you have ideas/requests for future extras, leave them in the comments! And yes, I will be doing a SHIFTERS version of this.