Here is what has happened at the start of the adventure.
Hundreds of years ago, the last remnants of the draconians knew that their race was doomed. All the nesting grounds had been shattered in the war, the land poisoned and turned to desert. The last survivors sealed away the artifact weapons in a tomb and engraved their sorrows on the walls. After decades sealed away in the tomb, the artifact weapons slumbered and their power faded. Over time, the tomb was buried beneath the sands.
Last month, that tomb was unearthed by archaeologists. The site is called Dig Site Five.
The archaeologists carefully avoided the traps surrounding the tomb at Dig Site Five. They copied down the engravings into a notebook. They unlocked the tomb, extracted the artifact weapons (still inert from their long years untouched by blood), and sent them to the museum at Miracle Spring for display to tourists.
The receptionist at the museum is named Edwin Digby; his cultist name is Brother Sandscour. He identified the artifacts for what they were, and sent a report to the researcher and cult leader Loflar Dalen (cultist name Brother Doomspeaker). Brother Doomspeaker marshalled a bunch of other cultists, and they charged into the museum in broad daylight, up to the second floor where the museum curator Martha Butler was reviewing the artifacts.
Brother Doomspeaker told Martha Butler that she was a fool who didn't understand the power she was holding, and then he stabbed her in the neck. Her blood spilled onto the ancient draconian artifact she was holding and awakened it. The Right Hand of Darkness, newly awakened, killed all the cultists it could find and then took Martha out for a rampage through the village. Its plan is to collect enough undead to form a ring around the village, preventing anyone from leaving as it kills them all.
In the meantime, the museum has not gone unattended. Brother Sandscour didn't have the courage to go up to the second floor with the rest of the cultists, but he went up after he left. He picked up the Left Hand of Darkness and let it take him out of the museum and into the village, where he's formed his own plan to kill people and raise an undead army.
After Brother Sandscour left, Martha's grandson Timmy showed up to meet her for lunch. Timmy picked up the Blade of Shadow. He's been playing quietly in the museum ever since, seeing clearly in the pitch darkness. He thinks he has a new toy.
More cultists will arrive at the museum soon.
In the meantime, Martha Butler's murder spree has brought her near the inn where the player characters are eating lunch. "I'm really sorry!" she shouts. "Run away! I can't let go of it! Run away before I kill you all!"
The player characters won't be doing that, hopefully.
It might be tempting to play cultists as some sort of grandiose villains with cunning, far-reaching plans. The cultists in this adventure are not that sort of cultist.
Consider: a cultist is someone who wants power so badly that they're interacting with an evil god to try to get it. This is an incredibly bad idea. This is the "Dear Sir, I Am A Prince Of Nigeria And I Have Seventeen Millions Dollars" of bad ideas.
The cultists really should know this, but they do not care, because someone said "power" and all their critical thinking skills have shut off.
These are that sort of cultist.