Several programs in Daphne and Antioch were led by a charioteer named Calliopas with this attribute, which also names a whale that Belisarius supposedly battled. An item decorated with this attribute marked the highest limit on Diocletian’s Edict on Maximum Prices. A product with this attribute was supposedly discovered by the philosopher Heracles after his dog’s mouth became stained during a seaside walk. The toga picta is distinguished by this attribute and was worn by generals celebrating a triumph. The future wife of Vladimir the Great, Princess Anna, was born in a chamber named for this attribute, for which she earned the epithet Porphyrogenita. The Phoenicians extracted a pigment of this color from Murex snails in Tyre. For 10 points, name this color associated with Roman royalty. ■END■
ANSWER: purple [or porphyry or purpura or purpureus; accept Tyrian purple; accept imperial purple or royal purple; accept “born in the purple” until read; accept Porphyrogenitus or Porphyrogenita until read; accept Porphyrios or Porphyrius or Porphyrion; accept Porphyrius Calliopas; accept violet or lavender or wisteria; accept mauve or thistle or phlox or heliotrope; prompt on color or colored; prompt on shade or hue]
<Other History>
= Average correct buzz position