The most famous one was MONTEZUMA but there were others of course, notably ATAUALPA.
The Aztec emperor at the time of the arrival of Hernán Cortés in México (1519) was Moctezuma Ilhuicamina, the son of Moctezuma Xocoyotzin (both are known in English as " Montezuma".)
The last emperor was Cuauhtémoc whose name in Náhuatl or Meshica (the language of the Aztecs, still spoken by a few hundreds of thousands in central México) means "Descending Eagle" or "Attacking Eagle". Cuauhtémoc was tortured and killed by the Spaniards shortly after the fall of the Aztec capital, Tenochtitlán, which is now Mexico City, the capital of México.
Atahualpa was not a Mexican emperor. He was the last Inca emperor in Perú and suffered the same fate than Cuauhtémoc in the hands of the Spanish conqueror Francisco Pizarro. I hope this helps. HandsomeVry