The Outlaws of Desolation Peak
The party was sent out to the town of Desolation Peak by The Twin Springs Mining Company to kill Black Jack Ketchum and his Hole in the Wall Gang. Black Jack had been terrorizing the mine and the company was losing money so they had no choice but to put a hit out on him.
The first stop in town for the party was the Holy Moses Saloon where they heard a rumor from two out of work miners that Black Jack had taken at least three shots to the head and survived the attack. The party realized that Black Jack's gang was a lot bigger than they had assumed and they also heard about some some crazy rock discovered in the mine that, when burned, seemed to emit a loud scream.
Eventually the party made their way to the Desolation Peak Hotel where they met Newton Earp, the brother of famed law man Wyatt Earp. Newton explained that he had written Wyatt, hoping he'd ride into town and put an end to Black Jack Ketchum but Wyatt never came and he received no response back.
After a long day, the party called it a night. The next morning they were woken up by gunshots coming from outside and when they investigated, they found that the Hole in the Wall Gang was robbing the bank and they had taken the bartender from the Holy Moses Saloon as a hostage. A quick plan was formed and then the party leapt into action taking out two of the ten robbers. After several rounds of bullets were traded back and forth the remaining bandits were able to take the money and flee. Thankfully the hostage was saved.
After the fight, the posse went to check out the mining offices and the foreman of the mine, Jonah Byrne, offered the players a sample of the strange rock and tipped the party off that gunpowder + strange rock + pressure = big boom. Lucretia, a member of the posse, comes up with an ingenious plan and the posse heads off to Black Jack's camp.
When the players reach the camp, Lucretia decides to sneak up the side of the mountain ridge near the compound and she instructs the rest of the posse to take positions on the ridge circling the encampment while she uses her knowledge of science to set up an explosion on the ridge and creates a rock slide that ends up blocking the entrance of the encampment and trapping all of the bandits inside.
In the middle of the commotion, the party spots Black Jack walking out of his tent. One of the players throws a bomb made out of gunpowder and the strange rock into the encampment and it lands right at Black Jack's feet exploding and killing several nearby bandits. Everyone started to celebrate, but then they realized that, against all odds, Black Jack was still standing, though he had lost a leg and one of his arms was now completely skeletal.
The rest of the team started pelting the encampment with dynamite procured from the mining company but Black Jack weathered the assault taking 2 or 3 more point blank dynamite blasts before falling to his knees. A member of the posse then lets off a once in a lifetime shot straight through his brain causing Black Jack Ketchum to explode and turning the entire camp into a crater.