On the edge of Mexico City's famed Zócalo plaza, next to the ruins of the Aztec sacred pyramid known as the Templo Mayor, the remains of an animal—perhaps a dog or a wolf—were discovered.

But Aztec starter Omar Serrano got Bryce Matthews to pop up, then got Jackson Waller looking to escape. Wolf Pack starter Casey Burfield got through the second, but ran into trouble again in the ...