Carlos Ometochtzin (Nahuatl for "Two Rabbit"; pronounced [oːmeˈtoːtʃ.tsin]) or Ahuachpitzactzin, or Chichimecatecatl (Nahuatl for "Chichimec lord," is also known simply as Don Carlos of Texcoco, was a member of the Acolhua nobility. His date of birth is unknown. In dispute is how old he was when he was executed by an episcopal Inquisition. He is known to history for his resistance to Christian evangelization. He was burnt at the stake on November 30, 1539, at the order of Bishop Don Juan de Zumárraga, the first Catholic bishop of New Spain, for continuing to practice the pre-Hispanic religion. The main source of information on Don Carlos is the record of his inquisition trial, published in 1910 by the Mexican archives.

Don Carlos was a grandson of the famous Texcocan ruler Nezahualcoyotl through his son Nezahualpilli. He held significant lands in the Texcoco region, his lands are depicted in the Aztec codex known as the Oztoticpac Lands Map of Texcoco, from ca. 1540 just after his execution.