All Myths Are True Modern Fantasy Setting

[Ash Mantle]

I have a confession to make, I really like the modern fantasy genre possibly even moreso than traditional fantasy at this point. However, within the framework of 5e not a lot can be found with modern fantasy in mind.
This is such a ripe and creative field to draw from and be inspired by, especially since I envision that all myths are true, and there are so many unexplained mysteries existing in the modern world. As all myths are true, so too are all conspiracies true. And if all myths are true, maybe none of them are true

One question to be asked is where did all the magical races go and why can't we perform magic now?
I envision that some of the more magical races, like elves, had already left via great portals that once connected our world with Realms that have since been Forgotten and also ventured into other worlds through great connecting gates. Perhaps the lineage of these magical races still lives on in us. You can see a supernatural litheness in the gracefulness of a certain ballerina, or a supernatural strength in a certain wrestler. There are also rumours floating about of a certain SWAT member who can casually walk into darkness without the aid of a flashlight or night vision googles.
And perhaps these magical races haven't really left, but still live and breathe amongst us even now.

As for magic? Magic hasn't died, we just don't see it as we walk by, blind in our glass and steel world. Magic still remembers us and still loves us.

Adventuring ideas in this setting could be that you are all operators working for an organisation designed to keep the supernatural quiet.
You could be monster hunters.
You could be the Fox Mulders of the world and trying to root out and expose conspiracies and organisations like the Men in Black, Majestic 12, etc.
You could be relic hunters, adventuring to sequester them in warehouses.
You could be explorers wanting to uncover and expose cryptids and unexplainable mysteries and beasts.
You could a student of a magic school like Hogwarts, or you could be a lone wizard adventuring with friends like Harry Dresden.
You could be members of an organisation tasked to find out what the Dyaltov Pass incident was, or any number of unexplained mysteries.

I think the 5e framework would work well with modern fantasy, and especially these rules in addition to the base 5e rules.

Things like The Yellow Road and Mister Tall could be things you might encounter.

 

[Ash Mantle]

Theories Concerning the Sphinx of Giza

The stones used to carve the Sphinx at Giza originated not from this earth but from the same dark and empty space holding Orion's belt.

Flung embedded in an asteroid and across the eons of antiquity, it is rumored the Sphinx took shape not from mortal imagination but from psychic impressions inexorably transfixing the brain - the artisans involved in the making of the Sphinx freed its image from the asteroid.

Any with psychic potential or awareness standing in front of the Sphinx have their minds bled into, and a strange black oil - later seen on MRI - replaces the body's cerebrospinal fluid. These individuals develop psychic gifts - prophecy, mind-reading, mesmerization, telekinesis.
Curiously, out of these psychically sensitive few, there are a handful whom the Sphinx seems to reject - causing the brain to be rent from the body and contorting the torso and limbs so they look nothing more like over long tendrils.

The dreams these psychically gifted have are replaced by the Sphinx with nightmares of twisting mazes and non-euclidean obelisks.

Something in the recent past has caused the nose of the Sphinx to break apart from the structure, sending odd-shaped cracks around the face, almost like grasping entwined claws, and made what looks curiously like yellow-parched flesh appear visible.

This has caused the Sphinx to fall oddly silent

 

[Ash Mantle]

Windows and Doors

Eyes are the windows to the soul, it has oft been repeated. But sometimes, these windows turn into doors, allowing reprehensible entities a course into our world and into us.

Ever wondered what that faint, red glint of the eye was when photographs were processed?
It was not your friend, your parent, your sibling staring back at you, It was something else, something other, and it knows you, has studied you through the veil between worlds and it is hungry.

 

[Ash Mantle]

MOKELE-MBEMBE

The trackless jungles hide many mysteries. From civilisations devoured by verdigris to entire cultures entombed beneath virulent fungi, the humid forest weeps for the covered past and entrapped future.

It is a place of plenty, of vitality yet also desolation. Numerous expeditions have braved these unknowable green oceans to extract quantities of treasure or knowledge. What most have found is death. Brought low by plague and parasites, these explorers only hear rumored echoes of a creature sustained by legend and myth.

These seemingly fanciful stories, told by local pygmy tribes, tell of a monstrous serpentine creature that lumbers about on four colossal legs. Repeated throughout these tellings is the ferocity of the creature and the ease in which it submits to violence in defending its territory or driving off interlopers.

These tales tell of a single protruding horn, wickedly sharp, that the creature rams into the flesh of its antagonists, leaving them broken and limp upon the air as it throws its head back in a roar of exultation. After which it would heave the body onto the ground so that it may feast upon the remains.

These pygmy tribes have a name for this creature, the mokele-mbembe, He Who Stops the Flow of Rivers.

Superstitions flit around the mokele-mbembe like moths attracted to flame. Eating the flesh of the mokele-mbembe in particular is considered taboo. An oral fable speaks of a tribe of victorious warriors who won against the predations of the mokele-mbembe and hewed its flesh into chunks to be cooked and eaten.
This ceremony was conducted with great fanfare and the choicest cuts were given to the mightiest warriors. They were found dead the very next morning, their forms contorted in agony.

Cryptid. It is said that cryptids only exist in rumours and whispers - that wholly unreal, cryptids are a product of fevered imaginings. The truth is that cryptids are remarkably and masterfully adept at remaining unseen and undetected. Cryptids possess a particular suite of traits that aid it in its obscuration from prying eyes.

MOKELE-MBEMBE
Huge beast, unaligned
Armor Class 13 (natural armor)
Hit Points 161 (14d12 + 70)
Speed 50 ft., swim 50 ft.
STR 26 (+8) DEX 10 (+0) CON 20 (+5) INT 2 (-4) WIS 12 (+1) CHA 10 (+0)
Skills Perception +5, Stealth +4
Senses passive Perception 15
Languages —
Challenge 9 (5,000 XP)

Innate Spellcasting. The mokele-mbembe's spellcasting ability is Wisdom (spell save DC 13). The mokele-mbembe can innately cast the following spells, requiring no material components:
3/day each: pass without trace

ACTIONS
Multiattack. The mokele-mbembe makes two attacks: one with its horn, one with its stomp, or one with its tail. It can't make both attacks against the same target.

Horn. Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 21 (3d8 + 8) piercing damage.

Stomp. Melee Weapon Attack: +12 to hit, reach 10 ft. Hit: 30 (4d10 + 8) bludgeoning damage. If the target is prone, The mokele-mbembe can make one stomp attack against it as a bonus action.

Tail. Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 21 (3d8 + 8) bludgeoning damage. If the target is a creature, it must succeed on a DC 16 Strength saving throw or be knocked prone.

 

[Ash Mantle]

Horrors in a Sleep Disorders Clinic

Personified nightmares

Bogeyman under the hospital beds, or in closets

Dimensional gates under the hospital beds, leading to the Dreamlands

The Sandman

Staff forcibly having the patients undergo the Russian Sleep Experiment

Dreams and reality blurring into each other, drawn maps and schematics are erased or new rooms and doors spring up where none existed

In nightmares, every choice you make is wrong

Hallucinations, hallucinations everywhere

Shadow people

Sleep paralysis, and no other supernatural explanation

Inability to distinguish reality from nightmares, fake monsters turning into real ones and vice versa

Unexplained creatures and movement, but only seen out of the corners of your eyes

Entrapment, straps and wires and sensors from medical equipment restrain you

Why can't I wake up!

WHERE IS MY FACE?!

Did you just nod off? You've missed an hour

Things that invade the mind

There is a thing standing in front of your hospital bed, it's right there, but because of your surroundings you can't really see it. Why can't you see it, it's right there!

You see there is something beyond the veil...

Hauntings

The place is infested with doppelgangers