Uitzilopochtli [Vitsli-putsli]

 The "blue hummingbird of the left side," this (Mexican) Aztec war god represents the sky, the young sun, and fertility. Worshippers made an image of the god of bread dough, which was then broken and eaten.

Uitzilopochtli figures in some Faust legends as the spirit of Hell, the first helper of Satan. Notice what happens when Berlioz mentions him in the first scene.

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