There are 13 tribes in total to secure variety of the game (You know, 13 is a pretty spooky and magical number, right?). The whole game is also influenced by 3 prophecies that are revealed ahead of time and fulfilled when the time is right. These prophecies give players other opportunities to score points, but also lose points if the players don't prepare themselves for the prophecy effects. Again, there are 13 prophecies in the game altogether (Woohoo 13 again!). This expansion also have new components to allow 5-player game version and several new buildings.
A new tribe and a new prophecy for Tzolk'in: The Mayan Calendar - Tribes & Prophecies. With tzolk’in: tribes and prophecies, players become the mighty leaders of their own tribes, caring for the Welfare of their people. Each tribe has unique gifts. Players can lead the wealthy ixtab, the numerous yaluk, the industrious ah chuy kak, or any of the 10 other tribes. Wise leadership will be needed, for prophets have foreseen three calamities that will befall the Maya. Those who neglect the prophecies shall perish, but those who heed the warnings and plan ahead shall lead their tribes to greater glory.