The Sioux
Leader
Chief Sitting Bull
UA
Great Buffalo Hunt : Starting with your second City, settling near Plains Tiles will spawn a Bison Resource. Bison in Sioux territory may no longer be improved but instead provide a large base tile yield and periodically roam throughout the map.
UU 1
Strong Heart : Replaces Knight. Can receive defensive bonuses. +25% vs Gunpowder Units. The first Strong Heart trained will also act as a Great General, providing a combat bonus to nearby land units. If this unit is killed the bonus transfers to another random Strong Heart warrior.
UI
Tipi : Available at Trapping. +1 Food. +1 Food, +1 Culture after Horseback Riding. If built near a City near which Bison/Wild Bison are also present, you have the option to move 1 Population from your largest City to the Tipi City. On City capture, all non-pillaged Tipi in the City Radius are removed. 1 Population per removed Tipi is redistributed to your remaining Cities.
The Sioux were a civ in the Civ Battle Royale. It is currently eliminated in 32nd place, after being revived twice. It's original capital was Hunkpapa. It was lead by Sitting Bull.