Chaac (also spelled Chac) is the name of the Maya rain deity. With his lightning axe, Chaac strikes the clouds and produces thunder and rain. Chaac corresponds to Tlaloc among the Aztecs.

Like other Maya gods, Chaac is both one and manifold. Four Chaacs are based in the cardinal directions and wear the directional colors. In 16th-century Yucatán, the directional Chaac of the east was called Chac Xib Chaac 'Red Man Chaac', only the colors being varied for the three other ones.

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