Ahuizotl is a character introduced in the sixteenth episode of Season 2: "Read It and Weep." Ahuizotl is a character in one of the Daring Do books, which Rainbow Dash reads while recuperating in the hospital. He is a malevolent creature with a hand on the end of his tail, who commands a pride of felines, including a tiger, a panther, a lynx, a cheetah, and a white house cat.
In the book, "Daring Do and the Quest for the Sapphire Stone," the titular pegasus first evades Ahuizotl and his pride of cats before infiltrating an ancient temple. Her goal is to retrieve a blue stone statue in the shape of two canine figures sitting back to back, something Ahuizotl also covets.
Ahuizotl is based upon the mythical creatures of the same name from Mesoamerican folklore. They were said to be able to mimic the voice of a young child, and to lurk under water near the banks of rivers and use their hand-tails to drag unlucky people down and drown them. The ahuizotl would then devour their fingernails and eyeballs.
In Season 4, Episode 4, "Daring Don't," it is revealed that Ahuizotl is a real creature, as is his nemesis Daring Do. Ahuizotl is attempting to collect the Rings of Scorcherro but is foiled by Daring and the Mane Six.
Ahuizotl speaks with a distinct Spanish accent, and commands a tribe of earth ponies with a Mesoamerican culture, in addition to his pride of cats.