Red Dead Redemption 2 features different optional missions, known as Stranger missions, where you must help a variety of interesting individuals with their troubles. The Wisdom of the Elders is a rather straightforward Stranger mission.
The Wisdom of the Elders is only available from Chapter 5 onward. The mission can be started right after having completed the Fleeting Joy mission late in the chapter.
To begin it, you must head to the train track to the west of the Van Horn Trading post. Here, you will see a man in a state of confusion who is unable to communicate properly with Arthur, repeating the name of his village over and over. Pick up the man and put him on your horse, then head to the man's village, which will be marked on the map.
Once at the village, another man will approach you, but things seem to be much more complicated since the man you are carrying will attack you. Just knock him to complete the first part of the mission.
The second part of the mission is unlocked after one full day has passed since the first part has been completed, and it can only be started during night-time.
Head into the village and speak with the village elder, a person called Obediah Hinton. Hinton doesn't seem too open to the idea of talking to strangers, as he only mumbles about demons. Right after this, Arthur will hear a woman screaming for help: the village is being overrun by rabid dogs.
The dogs are marked with red dots on the map: there are two attacking pigs, five more by the bridge, and four inside the village itself. The dogs are quite fast, so make sure to use Dead Eye to dispose of them quickly.
After you have dealt with all of the rabid dogs, a Shaman will appear. He apparently warned the villagers about a curse, but they didn't listen to him. He then shows a weird charm to Arthur, telling him that destroying all such charms can lift the curse.
The third part of The Wisdom of the Elders mission can be started right after completing part II. The only thing you have to do to complete it is to find and destroy the 13 charms to lift the curse from the village.
The charms are located very close to the village. There are six to the north of the river, two inside the river and five to the south of the river. Finding them is rather easy, as they will be marked with a red dot on the map once Arthur gets close enough to them. You can also use Eagle Eye to highlight them while exploring. Due to the environment, we suggest you search for these charms during night time, as they become slightly easier to spot.
This part of the mission becomes available right after gathering all the 13 charms and completing the previous one.
Once you get all the charms, head back to the village to speak with the Shaman and Obediah. Finding the charms made things even worse than before, sadly, as the dark spirits have apparently been set free and are wreaking havoc in the village.
At this point, Arthur has had enough of the whole situation, understanding that something weird is going on. The outlaw will threaten the Shaman, who will then flee. Obediah will tell Arthur that the Shaman told the villagers to never enter the nearby mines and that is exactly where we are going now.
After part IV of the mission has been completed, you can start part V right away by heading into the mines marked on the map.
While getting close to the mines, Arthur will hear some coughing, realizing that the water has been poisoned, which is what is making the villagers act crazy. The outlaw will fill a bottle with the polluted water to show as proof and notice that a man has fled the mines.
As soon as you regain control of Arthur, proceed through the caverns as quickly as possible, as health will drain slowly during this sequence due to the poison in the air. You will eventually emerge - at this point you should call your horse.
Back at the village, you will find the Shaman who is trying to make the villagers sign a contract. Arthur will expose the Shaman's lies and force him to drink the poisoned water stored in the bottle. The Shaman will confess and then die due to the poison. At this point, collect the contract and the $50 to complete the mission.