William Fash writes: "The final version of the Hieroglyphic Stairway was built by Ruler 13 [18-Rabbit or Waxaklajun Ub'ah K'awil], not, as we and others had believed, in the years following his death. In re-modelling this ancient and revered edifice to honor the memory of Ruler 12, Waxaklajun Ub'ah K'awil felt compelled to compensate for burying Stela 63, and the Papagayo step, by creating a much more complete record of the city's dynastic history. In this innovative effort, he cited the birth, accession to power, important rituals and other achievements, parentage statements, and death of the most distinguished rulers in the city. Special interest was focused on his long-lived predecessor, Ruler 12.
Ruler 15 [Smoke Shell, whose stela stands at the foot of the stairway] subsequently doubled the length and historical content of the stairway inscription, and was likely also responsible for creating the balustrades that framed it. It was he who dedicated the final version of the temple of Structure 26, with its impressive temple façades, roof crest, and extraordinary interior inscription."
William L. Fash, Scribes, Warriors and Kings: The City of Copán and the Ancient Maya, p. 144-146