Although not standing at the time, Stela I was discovered by Stephens and Catherwood and is thought to have been originally erected in this niche. It was meant to be paired with the altar in the foreground, as the stela's inscription continues on the altar. The stela depicts a standing ruler whose face is covered by a mask of the deity known as Chaak Xib Chaak. It has been suggested that the ruler is wearing a mask to convey the message that he is already dead, but a Yaxchilan ruler wears an almost identical mask on that site's Stela 11 as he presides over three bound captives at a time preceding his accession, so the interpretation of the ruler being dead here is far from certain.