In the vast areas of the northern peoples, there is a rule that is taught from early childhood. Never go towards the Ashy Mountain. Don't think about it. Don't look into the shadows on its peak. Don't look at it at night. Run from it even in your sleep.
Otherwise they'll come for you. The men wearing animal masks, accompanied by the ancient monster shadows sent by the furious gods. They will make you one of them.
And it will be you who will guard the artifact that should not fall into the hands of any man, for the rest of your life.
Same rumors in different parts of the world give hope that the artifact the heroes are searching for is here. Its endless energy can be concealed only at the top of the Ashy Mountain, hidden far to the north. A thing that even the oldest of the gods are ashamed of can be only there, among the clouds. The object, the existence of which proves absurdity of worshipping the Almighty God.
The artifact that can bring back life.
The Ashy Mountain can hide the other artifacts, the ones that will be more suitable for your campaign.
THE DEEP NORTH
It's not enough for the heroes to go to a place where it snows all year round without a break. They need to go further; to go to the places that are hidden so deeply that only the dead know about the creatures living there.
Preparation. The heroes should prepare for such an adventure. The way will be harsh even to the last known northern settlement, not to mention the things what await them next.
Harsh conditions. The deeper the heroes move north, the harsher the conditions will be.
Introduce the COLD LEVEL as soon as possible and show it to the players. You can make it 10 points, where 1 - the heroes feel almost no cold and can move freely, 5 - the cold is significant and the heroes need very warm clothes and they get penalties for movement, 10 - everything around freezes and the heroes get serious penalties for ability checks and movement; it's almost impossible to walk and do something.
During the adventure, the cold level can increase or decrease depending on the weather and the depth of the heroes' journey to the Ashy Mountain. Hiding from blizzards, using equipment, and warm clothing, the heroes reduce their feeling of cold by removing negative effects.
Use the weather conditions to give your adventure dramatic effects. If the heroes can easily cope with difficulties and enemies on their way - a sudden storm can toughen their mission.
If your heroes have powerful magic that allows them to overcome these conditions easily - consider the effects of cold a strong magic that blocks these abilities.
HAIRUN MOUNT
Having gathered their wits and found the forgotten trails, the heroes will conquer the first peak, HAIRUN MOUNT, visible to them from afar. On the way up, the heroes will learn more about the northern people by stumbling upon the remains of the perished expedition.
THE WAY TO THE FOOT OF THE ASHY MOUNTAIN
To reach the foot of the Ashy Mountain, the heroes should go through dangerous ascents and descents, narrow canyons, and northerners' settlements.
Settlements of the Northerners. On their way, the heroes can find abandoned settlements of the northerners. There they can find valuable supplies, have a rest, warm-up, and learn a little more about the GUARDIANS - the northerners who protect these lands. However, not all of the settlements can be safe.
SETTLEMENTS OF THE NORTHERNERS
d6 Description
1 The inhabitants of the settlement fled, leaving some supplies and equipment, but there is no shelter here.
2 The village ruins are hidden in a windless place and are patrolled by the Guardians at night.
3 The abandoned hunting village with a secret shelter in the mountain. The heroes can find something valuable there.
4 The Guardians set up an observation point and bring the resources from other places here. Several groups are patrolling the vicinities.
5 Ruins of a large house indicate where one of the elders used to live. The heroes will find shelter and warm clothes here.
6 A place that seemed to be quiet and peaceful at first appears to be the beast's' lair.
Obstacles on the way. Frost will not be the only enemy of the heroes on their way to the artifact.
ENCOUNTERS ON THE WAY
d6 Description
1 Suddenly, a breakaway piece of the mountain blocks the heroes' way through the canyon. The noise draws the attention of the Guardians and the Ashy monsters.
2 The heroes find a deep rift, barely escaping from falling down. The only icy bridge nearby is guarded by the Ashy monsters.
3 A sudden blizzard splits up the group of the heroes, forcing them to look for each other when the Guardians on patrol approach.
4 A giant avalanche descends right on the way of the heroes. When they run into the nearest cave, they find hostile animals there.
5 The cave leading through the mountain turns out to be a small settlement of several families of the Guardians.
6 A rapid mountain river sweeping away everything on its way is blocking the heroes' way. Nearby, there is a large tree that fell across the river. The Guardians on the other side are waiting for the heroes to begin their life-threatening crossing to the opposite side.
ABOUT THE GUARDIANS
The Guardians - this is how the Northerners who consider the legend of Erna as a tale of the human's weakness in front of the fate call themselves. The heart of the fallen god cannot be returned and his strength is too great. The Ashy Mountain, the place where it lies, should be protected at whatever cost. The Guardians have sworn to do so for the rest of their lives.
United with the Dark. The enraged gods sent monsters to the northern lands to drive people as far away as possible from the evidence of their weakness. Having seen that some of the northerners were ready to give up their own lives to keep the secret, the gods spared them and turned them into their servants.
Under divine supervision. The Ashy monsters have allied themselves with the Guardians. In full obedience, they execute the commands of a creature called Oskuld - the divine incarnation that hides in the passes of the Ashy Mountain.
Fate thieves. Every few years, the Guardians and the Ashy creatures come down from the mountains to replenish their army with people from the northern tribes. They take away young and talented warriors and no one dares to resist them.
SPECIAL FINDS IN SHELTERS AND SETTLEMENTS
d8 Description
1 Very warm clothes of the northerners made of furs of local animals
2 Several enchanted stones that give heat for a couple of hours
3 Bow with special arrows that fly even through strong winds
4 A frozen disgusting drink that increases cold tolerance for a while
5 Sets of snowshoes and skis
6 Climbing kits
7 An amulet that hides a group of people for a few minutes (recharge time - 1 day)
8 A spear with an enchanted tip that can heat up to high temperatures and ignite even wet wood.
The beginning. The heroes will understand the danger of their mission when they reach the foot of the Ashy Mountain on its shadow side and see a pair of bright lights shimmering against the rocks.
When they look at the lights, the heroes will realize in terror that these are the eyes. The eyes of a huge white serpent OSKULD, looking around for uninvited guests.

ASHY WYVERN (difficulty 4/10)
A divine beast that can fly.
* Ashy breathing. Releases a powerful sizzling charge of ash that immobilizes the target for a while
* Kidnapping. Tightly grabs the victim and soars up in the air
* Intolerance for cold. While flying, the beast is vulnerable to cold attacks that force it to return to the ground
ASHY LYNX (difficulty 6/10)
A divine monster capable of tracking down the strangers
* Alarm. Feeling the presence of the strangers, the monster lets the nearest Guardians know about it
* Blurry silhouette. When running, the lynx's silhouette gets blurred, which complicates shots at it with a long-range weapon
ASHY WARRIOR WITH AN AXE (difficulty 8/10)
The Northerner who received the power of the Ashy Mountain
* Circular throw. Throws a giant axe that crushes everything on its way in a circle and catches it at the end
* Break. Passes through the surrounding enemies with a hitch and immobilizes their movements with solidifying ashes

NEUTRAL MECHANICS
The adventure is created without binding to any specific RPG system. You can easily transfer both gameplay features and numerical values to your preferred system. Use the aspects of characters and locations at your discretion, while disclosing or hiding what you want from the characters. Make the heroes pass checks or be guided by common sense - now it's your adventure!
IN SEARCH OF OBSCURE CYCLE
What lurks in caves that are hidden even from the gods? What happens if you go off a centuries-old trail, towards the unknown? What happens if you imagine, for a moment, that familiar places can still hide the ancient secrets? The cycle "In Search of Obscure" will test the character of your heroes, as they will face the things they haven't seen before, the things that will seem like a bad dream the next morning. And sometimes the heroes themselves will be their main foe.

Hello! We are trying different forms and shapes for our stories, so this is another try.
I hope you will like it!
Feel free to share your ideas and experience about adventure in the comments!
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