KAMO no Tadayuki was very good at 'sekifu,' a practice to guess an article inside a cover, and in the Engi era, he was ordered by Emperor Daigo, the emperor of that time, to show his skill.
賀茂忠行は覆物の中身を当てる「射覆」が得意であったといわれ、延喜年間に時の醍醐天皇からこの腕を披露するように命じられた。