Dark Souls RPG

The adventure can be based on Dark Souls 1 or its sequels, Dark Souls 2 and 3. Taking characters, more and stories from those canons

It is a dark medieval fantasy setting.

No NPC is under 100 years old, all of them being practically immortal undead, or gods, or dragons or something like that.

The curse of the undead is a mark that prevents a person from dying, but drives them mad, turning them into a violent zombie.

The secret is that it was placed there by Gwyn, the Lord of Light, to stop a cycle of darkness. This was before he sacrificed himself.

The mark spreads like a plague among humanity, those with dark marks. Everyone hates the undead, and since they can't kill them, they confine them far away or bury them...

Gwyn: God of light. He had several children and is the king of the Age of Fire. He sacrificed himself to keep the flame burning. He is the principal god. He fathered the race of the noble, endangered Aeres of Light.

Izalith: Witch of Chaos. She gave birth to seven daughters. From her comes the flame of chaos and therefore my demons. The flame of chaos was supposed to replace the primal one, but it went wrong.

Nito: Lord of the Dead. He created the Milfanitos and Fenitos. He watches over the crypts and the cycle of death in general. As the primal flame weakens, it loses its power.

Furtive Pygmy: Father of humanity and darkness

Fire that gave rise to souls, hidden somewhere. Gwyn and the primal serpent Kathe devised a system: Sacrificing souls to the flame to keep it alive. Gwyn was the first, but it is hoped more undead will do so to keep the flame alive.

Every time the flame is rekindled, it resurfaces with less force

When the flame is rekindled, the lords weaken, the seals that the gods place on humanity and darkness/humanity are strengthened (but it also becomes more chaotic)

Large, six-limbed stone creatures (two wings and four legs). They fought a war with Gwyn and lost. They're extinct. Drakes are their dumber, four-limbed cousins who still live.

Half animal, half humanoid. Result of the parasites that emerge from the chaos flame of Izalith.

Of Gwyn's clan, the best are the Silver Knights. An elite force, only after Gwyn's death are humans of darkness recruited.

Black knights are specters of silver knights left behind after a war against demons.

Beings of light, Gwyn's clan, look down on humanity. They appear human, but taller and with blue skin tones. With the decline of fire, there are fewer and fewer of them.

Church that worships Gwyn's uncle, the all-father, Lloyd. Some say it's a fraud.

Goddess of sin. She seeks to punish the gods for the imbalance they created by disrupting the light/dark cycle.

School of magic in the human kingdoms

False dragons. Giant serpents manipulate events from the shadows. Their leader is believed to also lead the Darkwraith faction and Londor.