Another addendum to the lore:

How the fuck does Cy exist???
(With pictures, of course!)

Lemme know if I should do one with common behaviors he exhibits and explain them bc I feel like I must lol.

Fair warning, this gets weird at the end.

First, basic anatomy:

Starting at the antlers.

Cylus had large, fuzzy antlers similar to tree branches. These have bioluminescent patches of fur in a speckled pattern, and curve forward to protect his head in combat. They exist for defensive and mating purposes.

Now to ears!:

Cy relies HEAVILY on his senses of hearing and smell to navigate the world. Because of this, he has very long ears that can swivel all around to locate sound.
The top pair is used to pick up noises and voices. The bottom pair is used to pick up vibrations
These can be used for body language expression too, as follows

Pinned: upset, angry, or scared
Tilted forward: interested or excited
Flicking: content and relaxed.
Top pair pointed up: he hears something
Bottom pair pointed down: he senses something nearby

Next is eyes:

Cylus has two pairs of eyes and one larger one in the center. This allows him to have a near 360* view of the world, as well as keep a tab on his surroundings while he rests. He does not have the best eyesight, so this is necessary.
The one in his forehead is covered with a thin blue tinted scale and does not close. The other 4 have eyelids but do not blink, only close to rest.

Arms:

Cy's arms are very long, and sport a wonderful black fuzz that feels like a combination of silks and velvet.
On the inside of each wrist is a small slat that molten metal silk comes out of. He is able to hold molten metal easily due to this fur and weave it into whatever he pleases.

Hands:

Cylus sports a wonderful set of non-retractable claws on each hand that begin halfway into his first knuckle. These nails are hollow inside and are used primarily for gathering food and kneading nests.

Down to his chest!

His shoulders and chest are lined with golden, reflective scales. These patches radiate heat, blush, and provide protection for him. Scraping an antler on the shoulder patches produces a loud hissing sound to warn predators.
Curiously, the scales along his chest seem to form a tight wrap around his muscle.

To his legs:

Cy's upper legs are a mix of skin, scale, and fur. His genetalia is hidden in an unnoticeable, dull scale patch, allowing for easy travel.

Halfway down the thigh begins another patch of that same silky fuzz, which continues down the leg and ends in a tuft around the hoof.

The leg shape itself if optimized for running and flying long distances rather quickly, being able to bend up toward the chest in the large center curve. Hooves are made of keratin, much like a horse, but wrapped in a natural copper shell to protect them from the elements.
Side note, Cy has a sensitive spot on the inside of his hooves that gets sore after a run.

To the extras!!

Cy has two types of wing.

The first pair, located high on his back, are black and gold passive soaring wings.
These wings are designed to stay gliding in the air for long periods of time and are used for travel, as well as balance.
These wings have a keratin nub on the pain joint by the flight feathers that allows Cylus to support himself and balance on them when crouching.
The gold coloration glows dimly like the scales

The second pair are brightly colored High speed wings located in his low back just within his waist. These wings have two functions.

These wings are designed to control the body at faster speeds and aid in travel with the passive soaring wings (pair 1) in cruise control.
The secondary purpose is to show off and attract a mate. The bright gradients on these feathers shine in the light and emit a soft, warm glow during dark hours.

The tail:

Cy's tail serves many purposes. The long furs are silk soft and gradient from black at the base to a bright, cheery gold, much like his hair. The main purpose of the tail is pup raising, as well as self regulation. It can be used to warm up a pup on cold nights, curl around his mate for added security, twine with another tail as a sign of romantic bonds, and cool himself off on a hot summer evening.

Now to the wonderful world of internal anatomy!!

Starting with the obvious: Cylus does NOT have human organs! He has a minimal amount of blood that flows through the head, neck, and extremities for hydration and fine motor control, but that is about it. Instead, he has the following.

Starting with the silk pouches:
When consuming material, Cy's body stores and prepares three different types of silks. These silks have specific uses when it comes to his life.

Top, Gold silk: used to make gifts and presents, impress a mate, or construct small trinkets. Main type.
Middle, Copper silks: copper silk is the weakest, and used exclusively on pups. This silk produces a healing effect and is used to bandage pup's injuries or give them something beneficial to chew.
Bottom, Titanium silk: Titanium silk is the strongest, used for construction of dens and irreplaceable items. These can be used as supports or framework, and is usually only used to create a safe den and nest for his family.

Moving to flame basin:

Cylus runs on warmth, without it he can fall into a process called brumation, where he essentially goes on pause until he becomes warm again.

The flame basin is a reservoir of foods that a large golden flame in his body runs on, which produces just enough body heat to keep him out of brumation. Eating large meals makes him warmer, and not eating makes him colder.
This is only necessary is his mate is unwilling or unable to warm him up.

Lastly, reproductive!
If you don't want to know weird genital things about Cy, you can end the chapter here. Last warning tho :)

Good luck. It's weird

Cy, per human definition, is a hermaphrodite. Meaning that he can both sire and produce offspring.

He does have human-ish male genetalia hidden in his pouch, which is proportionate to his average height of 9'6. However he does not possess testicles like humans do, as that system is internal.

Cylus also has a set fertility cycle. The best time for him to produce pups (the term for his offspring) is the summer, so the peak of fertility is during the spring. This is a very instinctual time and also a time when he begins to overheat. The only thing that can cool him down is the touch of a mate, which is the reason he goes absolute fuckin bonkers over any sort of loving during this time.
He can reproduce at any time of the year, though. Average "pregnancy" times are 4-6 weeks until an egg is laid, then another 3 weeks until it hatches.
So far there have been no species incompatible with Cylus. (The offspring might be weird as hell but hey, that's how you get nuclear fuckers like Caspin)

Now for the weird shit (I'm really warning y'all)

Inwardly he has a complex series of organs contained in a rather large spot about the size of a basketball. These are located halfway up his torso, closer to the silk pouches than depicted in the diagram.

There is one tract that leads to this system, located where you can probably assume it is given his status as a gay man.
There is an organ there that produces a small egg similar to a human female's once it senses fertilization. From there, silks are deposited and wrapped around the developing pup until it is fully coated in a gold and copper shell, when it is then laid.
Cy will proceed to guard his egg until it hatches.

Emilio, how did it get this detailed, you might ask?
I'm a veterinary student studying genetics, that's how-

Anyways, this has been the anatomy of a Cy, hosted by someone who has put WAY too much thought into this.