Similarities in certain paintings and sculptures created by pre-Conquest and early Colonial Aztec artists strongly suggest that the original identities and nature of the tzitzimime changed over the decades following the Spanish conquest. These images support textual evidence that Spanish authors, typically mendicants and clergymen, quickly conflated the tzitzimime with the Devil and his servants, in the process demonizing and ultimately masculinizing them as well. Whereas the most important tzitzimime were apparently female in pre-Hispanic times, Colonial authors writing after the mid-sixteenth century described them as exclusively or predominantly male. The potential for the tzitzimime terrorizing people during periods of crisis, when the sun's continued passage through the firmament was perceived as doubtful, became the sole focus of late-Colonial descriptions of the role and attributes of the tzitzimime. In pre-Hispanic times, in contrast, the most important tzitzimime were ambivalent creator deities whose generative powers rendered them capable of preventing and curing illness as well as causing harm. In the beginning, the tzitzimime apparently were female, the principal tzitzimitl, Citlalinicue, having passed on her powers to her daughters and granddaughters. These descendants included the goddess Cihuacoatl who, like the goddess Citlalinicue, was the patroness of parturient Aztec women and midwives and closely associated with the souls of women who had died in childbirth. Itzpapalotl is another example, to which we can add Tlaltecuhtli, Coatlicue, and Coatlicue's four self-sacrificing sisters. It was probably not until the Aztec government was in a position to rework official history that the national male deity Huitzilopochtli was inserted into Aztec stories of the creation in his manifestation as Omitecuhtli, “Bone Lord.” Like other tzitzimime, however, Omitecuhtli was petitioned to heal the sick, especially children, and was subsequently called upon to bestow his generative powers on newly elected government officials. These magical powers were embedded in the tzitzimime's garments. Their capes and skirts were decorated with skulls and crossbones that were often combined with symbols of stars and, occasionally, stone knives. This explains why petitions for a tzitzimitl's assistance were apparently made at a stone platform bearing these same designs. The platforms represented the sacred capes and skirts that, legend suggests, were the essence of the gods. Midwives and curers of both sexes probably made special use of these platforms, which provided them direct access to the tzitzimime. Materializing the sacred garments that embodied the generative essence of the tzitzimime provided the Aztec with a means of petitioning their assistance in averting illness and cosmic destruction.