Mashuka Vampires

In 721 A.E.M., when the Sacellum of Rimhr was making first contact with the various peoples in the northern portion of the continent, one group in specific interested them. These were the Mashuka, a nomadic group descended from the escaped slaves of the Verdant Willow empire. Nomadic groups were relatively uncommon in this area, as the soil in most parts of the northeast was fantastic for growing and roaming too far north would quickly put people in contact with hostile groups of Alquari. Still, though, the Mashuka wandered - a combination of social stigma and religious beliefs forced them into the lifestyle.

The Mashuka were very valuable sources of information for early conquerors from the Sacellum. Specifically, they gave insights on many of the other ethnic groups and were one of the few sources of intelligence on Alquari activities - part of their harvest ritual included foraging in the territory of the druids. During various interviews on this subject, there was a recurring word of advice:

leave the pumpkins in the northern forests undisturbed.

Yayoi Kusama

Part of the aforementioned stigma placed on the Mashuka were that they were carriers of vampirism, a disease caused by spiritual parasites infiltrating the bloodline. While this was rooted in truth, the bloodlines that did carry the disease split off from nomadic Mashuka groups very quickly. One of the locations that these fully-fledged vampires split off into was a particular section of the forest, where pumpkins grew. In time, the disease that caused vampirism adapted, infecting the seemingly-innocuous gourds.

Normally, this would be no problem. Vampirism usually can't progress past the dietary restrictions and aversion to sunlight without the use of magic that changes the form*. But pumpkins, for reasons beyond the world's best-versed scholars, are capable of magic. Whether this is an odd phenomenon present only within them, a worrying talent present in all plants, or the result of some outside force's tinkering is unknown.

( * - vampirism is a disease caused by spirits colonizing an organism. As such, at first it can only grant the adverse effects of being a vampire. However, all spirits feed on magic. Vampiric spirits have a taste specifically for transmutation magic that modifies the body. If one with vampirism feeds their disease enough, they will begin to reap the benefits of it.)

On full moons, or other occasions when the lines between the Material and Astral Planes were thin, natural magic lying dormant deep within the hearts of these pumpkins would begin to stir. Eventually, with additional urging from the spirits within them, they would begin to spellcast.

They would grow spindly limbs of wood, and red eyes would blink open inside their orange shells. Inexplicably, they would gain the ability to talk, and carve out faces upon themselves for which to see and speak with their sharp fingers.

And such were born the Willkhu - Mahsuka Vampires.

http://breebird33.tumblr.com/post/101376826957/happy-halloween-everybody

Statblock

If you need a refresher on how I do these, here you go.

Pumpkin Vampire

HD 3 Size Medium AC As Leather Speed As Wood Elf

Darkvision 60 ft. Dexterity 14

Claws: Dodge 14, 1d8 + Grapple

Jack-o'-Lantern - Dealing fire damage to a Pumpkin Vampire will cause its head to ignite (as a torch). This allows it to cast fire bolt once per turn as a bonus action. 

Vampirism - A Pumpkin Vampire may bite a target that is willing, grappled, or incapacitated as an action. This deals 2d4 necrotic damage and heals the Pumpkin Vampire for as much health. Then, the target must make a Charisma saving throw, DC 15. Those who fail are infected with Vampirism (drains one Charisma every ten minutes until you hit zero) for an hour. At the end of the hour, target makes the save again. If they fail, it becomes permanent, turning them into a Vampire Spawn (for PCs, this means they lose control of their character).

The Shadowfell's God

Shadows

The Shadowfell was born in the time of the Archlords. It began as little more than a corner of the Astral Plane, where dreams give rise to life. Alenta, the most human of the Archlords, claimed this corner of it for himself. He would use it to enjoy his privilege as a creator god, and to deny its use from his fellows. Most of them would use it for nothing but ill.

...but he found that he could not use it. Alenta was by far the least interested in this pantheon with the business of creation, but here when he put an effort forth nothing happened. The plane writhed, contorted to avoid his attempts to create a mental progeny. It rejected him, and stayed barren. Frustrated, Alenta warded the place off from the other Archlords and abandoned it for more hopeful pursuits.

When he left it unchecked, it began to fester.

Alenta's folly was that he attempted to create life through magic. He tried a physical creation of life - to craft flesh and bone into a recognizable form. The Astral Plane does not play by such rules. It is the kingdom of dreams. The tangible has no power there. But still, residue from his efforts eventually manifested as a race known as Shadar'kai.

Another side effect of Alenta's attempts at creation were a distortion of this section of the Astral Plane's metaphysical methods. The will of an Archlord is not so easily resisted, and the plane had to change itself to overcome Alenta's primal magic. So, this section of the plane broke itself off. Going even further, it took on a niche. It would not create life from just any dreams. Exposure to Alenta's blackened machinations meant it would only accept nightmares as fuel for creation.

Millennium passed. Mortal night terrors birthed a menagerie of horrors within the Shadowfell, and where they could Shadar'kai built up their civilizations. This relationship was... unsustainable. Eventually the Shadar'kai learned of their origin, and called upon their creator god. Alenta, surprised that the territory he'd neglected had grown fruit, discovered the beasts on the plane and quickly plunged it into a civil war.

Blows were exchanged. The Shadar'kai, reunited with their god, fought against the rest of their world. Legions were slaughtered and rebuilt in days on both sides. The stalemate calcified, until the civil war was nothing more than worthless bodies being thrown at each other.

This is when the Egg hatched.

Madness

The Shadowfell has a habit of recreating locations on the Material Plane imperfectly. One such location was the Divine Womb, the birthplace of Loom's gods. The mechanics of that place are outside of the scope of this post, but thankfully the Shadowfell's distorted mirror of it function in very simple terms.

Instead of a Womb, the Shadowfell had a Divine Egg. A singular, massive embryo, holding an incubating god. Whereas Loom's gods were born from mortal hope, the Shadowfell would only release its god when the plane was completely hopeless.

Divine Wombs will give birth to a Lastborn God at the end of their planet's lifespan, but the Shadowfell contained only a Firstborn God. As opposed to being the synthesis of its planet's history, the Firstborn God would exemplify everything the Shadowfell isn't. And it would bear the visage of its greatest criminal.

The Shadowfell was a place of madness and shadows. Alenta had rendered it such when he tampered with forces he didn't understand, and then returned only to plunge it into hopeless war. And so the Divine Egg finally cracked open, giving birth to his only son: Alentyan, the god of Light and Wisdom.

Peter Mohrbacher

After this event, Alenta's interest in the civil war dwindled. He departed the Shadowfell in disgrace, and his people followed suit. They went to Vessel, one of Loom's three moons.

Alentyan left as soon as he was born. He had no purpose here. Its denizens cared not for either of his disciplines. The Material Plane was much more accommodating, and that is where he resided for thousands of years. He was a sage for those who sought him out, bringing illumination to those he deemed worthy. He lacked interest in the position of "god," but when a council of others like him sought to care for the planet in its darkest hour he found no good reason to exclude himself, and took his place among the Thirteen.

The Shadowfell stayed as it had been after Alenta left. A small group of belligerent Shadar'kai remained to continue fighting against the beasts they could take on. It produced the finest monster hunters in the planescape for generations to come. 

Dreams cannot be tamed, even by the divine. Light and wisdom will always flee from a place of shadows and madness.

The Mourning Blade

This is a magic item. It's also an experiment with magic weapons, where they start out with minor effects but "level up" as you use them to gain cooler powers.

Source: rockydesign on cgtrader

The Mourning Blade is an artifact of the Mourn family, a lineage of elven spellswords. It is usually kept locked away, for it is only given to those who have truly learned the price for taking a life. The hope is that, once you have it, you never use it.

Of course, the people who wind up finding it probably aren't of the Mourn lineage. For them, it's just  a Longsword +0 (counts as magical for overcoming resistance/immunity) that can shine light out of its eye, as per the light cantrip (or, lacking that, a torch). You may activate or deactivate this ability as a bonus action. You may only use this feature for an hour, after which this ability is disabled for 24 hours. When this also happens, it also cries a quicksilver tear.

Quicksilver tears restore a spell slot when consumed. The level of the spell slot is your choice. When you do this, you take 1d6 poison damage per level of spell slot restored. Against non-magic users, it is just a poison that deals 3d6 damage.

The first time you kill an enemy with the Mourning Blade, it cries a quicksilver tear. This will drip down onto your skin, automatically administering the effects to you. It also turns your eyes the same color as the sword's eye.

The second time you kill an enemy with the Mourning Blade, and every time afterwards, you cry a quicksilver tear. You may consume this tear on the same turn as the killing blow as a free action.

The third time you kill an enemy with the Mourning Blade, and every time afterwards, it becomes a dancing weapon that will automatically attack any creature that comes within 10 feet of the newly-made corpse. You have until the end of your next turn to get out of the area, or the sword attacks you. You cannot wield the weapon again until combat ends.