Three thousand years ago, Yaotl (today known as Max Winters) and his siblings Gato, Serpiente, Mono, and Aguila, learned of a special constellation called The Star of Kicaan, which aligned every three thousand years to open a portal to another dimension. Yaotl had managed to retrieve the devices used to attract the portal's energy, and timed the release of the portal with their attack on an enormous and powerful city by the name of Xalica with the alignment of the stars. The portal opened and many different types of species from other dimensions emerged from it, destroying the opposing army, yet also attacking Yaotl's also. The portal also unleashed energy upon Yaotl and his brotherhood, granting Yaotl immortality, but turning his brotherhood into stone. These curses would remain in place until the thirteen monsters were sent back to the portal.
Three thousand years later, Yaotl sought to rid himself of his immortality, going by the name Max Winters, and found his brothers and sister to get the 13 monsters that were released years ago, and managed to get 12 of the beasts. However, Aguila started to suspect that their brother was going to get rid of them to keep the immortality for himself, not realizing that, once the monsters were sent back, Winter's immortality would be lifted as well.
It eventually turned out that Winters was trying to get rid of his immortality, to redeem himself for the damage he and his siblings had done, but the siblings believed he had gone soft and weak, and still thought they should keep their immortality and continue their conquest to take over the world. Eventually, they were sucked into the vortex with the monsters, and became human again. The Stone Warriors are excellent in battle as it's seen in the beginning of the movie. During the hunt for the 13 monsters, they take the monsters down fast and easy by themselves while the Foot take the beating for them. All of their eyes are glowing red and on their chest you can see a medallion that's glowing red, which might be their hearts, but it's unknown where Max Winter got them from. The Stone Warriors move fast in battle even though they are now made of stone.
- Aguila, Serpiente, Mono, and Gato are Spanish for Eagle, Snake, Monkey, and Cat, respectively.