I confess it's a difficult story line at first because many of the videos appear to run out of sequence or simply not fit together.
Here's my take, but I could be wrong. This is not a linear series where the plot is easily grasped:
In the days of the Hatfields and the McCoys and their feud, a number of humans have the ability to take on the shape of legendary archetypes. Chalchiutlicue (aka Calamity Jane or Calamity Jade) is an anthropomorphic basilisk lizard and symbolizes the goddess of landlocked waters and storms. In the video Tlaloc's Test: No Evil 007 Calamity gains a powerful talisman that allows her to manipulate water.
Other characters symbolize other gods, goddesses, or archetypes: Huehuecoytl (Huey) is a trickster coyote, Kajortoq (Kitty and also my favorite character) represents the various fox spirits in multiple cultures, and Quetzalcoatl is an anthropomorphic rattlesnake who is an archetype of the god of wind and corn. There are a number of others and they are all well fleshed out with full personalities and the voice actors are perfect.
The main conflict deals with a type of infection symbolized by a black oil that has invaded the land and the group struggles to rid the land of the evil while also dealing with the famous Hatfield/McCoy feud, a patchwork girl in search of a mother, and sometimes their own self-defeating behaviors. Gods they may represent, but they are far from perfect.
Give the series a try. Even if you don't grasp the storyline, the dialogue and the animation are a delight.
The video below, the first of the series, starts with a very young Kitty reliving the fable of the fox and the grapes and introduces us to the evil darkness that threatens the land. Start the video and let it run. It will play the entire series for you.