Istakwənayə

An istakwənayə or istakwenaya (Məskookei: [ɪstɑːkwənɑːjɑ]) (also transcribed estakwvnayv) is the horned snake of Southeastern America. The snake lives in the water, has horns like a deer, and is covered with iridescent, crystalline scales and a single, large crystal in its forehead. Both the scales and crystals are prized for their powers of divination and the horns are used in medicine. The istakwənayə is omnivorous, its favorite food being sumac. It does not harm people but seems to have a magnetic power over game.

Albaamaha
Around the central Gulf Coast, horned snakes are called ccinto sakcco (also tcinto såktco)  'crawfish snake' by the Albaamaha. There are four varieties, each with different horn colors: blue, red, white, yellow.

Koyaha
The Koyaha make effigies of horned snakes fashioned from stuffed deerhide, painted blue, with the antlers painted yellow. The Big Turtle Dance honors the spirits of the horned snakes for protection from storms, thunder, lightning, disease, and for the blessing of rainbows.

Aniyə̃wiya'i
The northern horned snake is called an ugdena by the Aniyə̃wiya'i. There are fewer of them but they have grown as large around as a tree trunk. The crystal on its forehead is a bright blazing crest and its scales glow like cinders. It has rings or spots of color along its whole length. The ugdena cannot be wounded except by shooting in the seventh spot from the head, because under this spot is the heart.

The crest of the ugdena is called an ulun'sudi ('transparent') and grants the bearer the power of being a wonder worker. Anything that looks directly into the reflected light from the ulun'sudi will run toward the snake with madness. Unlike their other horned snake cousins ugdena can release a foul cloud from their mouth that kills with poison. Even seeing an ugdena asleep will bring a curse on one's family.

Lakota
In the Black Hills there is a variety of horned snake called an ũhcherila/uŋȟcéǧila [ũχˈtʃeʁila]. The females are the most aggressive, but the males are called ũtehi. The female ũȟchérila can take a smoky or misty form that it uses to stalk its prey. Their eyes will still glow firey in the light. Ũȟchérila are as large as ugdena yet their scales are nearly impenetrable. When they attack they can manifest loose, smoky arms with black claws and their growl is like thunder. A person that looks on the fully visible form of an ũȟchérila will be struck with a blindness and insanity that usual kills its victims by the fourth day.

Like the ugdena, behind the seventh spot down its body from the head is the place to strike it. It will have a red gemstone under the skin for a heart. A sacred/medicine arrow is the only thing that can damage it. The warrior that takes it will be granted great strength. Warriors are also told by the weasel spirits that if they are swallowed by an ũȟchérila they should have time to cut their way out with a knife (as they are not poisonous like ugdena).

Ũȟchérila can take on giant bears. The largest giant bear to live in the Black Hills was killed by the largest ũȟchérila and once it decayed, the soil and rock piled up on its bones and formed a Bear Butte. The skeletons of ũȟchérila can also be found throughout Makȟóshicha.