The Jaguar Baby vessels belong to a large corpus of Late Classic Maya pictorial ceramics dubbed Codex-style pottery and originating from archaeological sites, such as El Mirador and Nakbe, in the north-central area of Peten, Guatemala, where they were made for a brief period shortly before and/or after the turn of the eighth century AD. Through strategic juxtapositions of images and words, the vessels convey the story of a rain god and a death spirit who, in the darkness between the sun’s setting and dawn, sacrifice an infant, a jaguar, or an infant with jaguar traits on a mountain in the midst of water, as an offering during the conjuring of an elderly deity. New evidence from a fragmentary Codex-style vessel recovered from the site of Calakmul in the southern half of Campeche, Mexico, suggests that the sacrifice is part of a pre-accession ritual serving to endow royal heirs with the ability to conjure, which, in turn, was integral to assuming the throne. / text