why did the aztecas move out of here

Jan 22, 2013
okay so we know there is azteca ruins and mummys and we also know there were still living ones to shibalba but why did they move out of the skull island skyways and into azteca? there were clearly none left when the first settlers arrived in the skull island skyways. did they all die? and if so how? :/

-jack nightgale lvl 42