Most sources agree that Tizoc took power in 1481 (the Aztec Year "2 House"), succeeding his older brother. Although Tizoc's reign was relatively short, he began the rebuilding of the Great Pyramid of Tenochtitlan (a task completed by his younger brother in 1487), and also put down a rebellion of the Matlatzincan peoples of the Toluca Valley. According to the Codex Mendoza, during Tizoc's reign the āltepēmeh of Tonalimoquetzayan, Toxico, Ecatepec, Cillán, Tecaxic, Tolocan, Yancuitlan, Tlappan, Atezcahuacan, Mazatlán, Xochiyetla, Tamapachco, Ecatliquapechco and Miquetlan were conquered. His rule was marred by the humiliation he received in his coronation war: fighting the Otomies at Metztitlan he brought home only 40 prisoners for sacrifice at his coronation ceremony. After this defeat Tizoc had to fight principally to maintain control of the already conquered territories, and failing to subdue new towns he was replaced, possibly poisoned, by his younger brother Ahuitzotl.