• Government Type: Monarchic Diarchy
• Symbol: Ouroboros & Five Suns
• Major Races: Elementals, Humans, Lizards
• Major Cities: Ozomatli, Quetzalcamina

Scattered across Splint are pools within sinkholes, known as cenotes. At the right time, and with a little luck, leaping into one of these cenotes will lead one to the vast underground realm of Itlan-Youali. One might expect these caverns to be desolate and dark, like most caves, but Itlan-Youali is anything but. Veins of gold-obsidian carved into intricate shapes deliver light below like several small suns, supporting a lush tropical landscape. The islands of Itlan-Youali float, magically suspended in a thick mist. Some believe that this mist leads to the Kurago, or perhaps the Dreaming. Accounts from those that have descended and survived are discombobulated and confused.

Within these dense forests live the mystical alebrijes, as well as multitudes of small dinosaur species. Most impressive, though, are the cities rising above the trees. Itlan-Youali has two capitals, each equal in dignity and power. Despite being aware of the surface world and overall receptive to the occasional visitor from above, Itlan-Youali remains staunchly neutral in world conflicts, refusing to assist Splint in its plight or take a side in any war.