Quetzalcoatl
Quetzalcoatl (KETz-uLL-koAT-L) is the Mesoamerican god of wind and knowledge. AD&D's Deities & Demigods describes him as "the mightiest god of his mythos," but like many things from that era of D&D the truth is a little less cut-and-dry. In Aztec mythos, Huitzilopochtli (WITs-ee-low-pocht-lee) is the god of War and Sun, who is arguably much more powerful.
Quetzalcoatl gets used as the patron deity for Lizardmen in pretty much every fantasy setting that has them, mostly because it's the only Aztec god that most GM's can pronounce. If you're running a setting utilizing Aztec or Mayan culture, he's an auto-include in your pantheon. It is worthy of note that Quetzalcoatl is largely opposed to human sacrifice in most of the myths involving him.