Note to JULIUS CAESAR, 5.1.62, 'a masker and a reveller'
A "mask" is a costume party, especially one in which people take part in skits. A "revel" is a boisterous party.
Antony had a reputation as a party animal. Plutarch wrote that the Romans "did abhor [Antony's] banckets and dronken feasts he made at unseasonable times," and that "in his house they did nothing but feast, daunce, and maske: and him selfe passed away the time in hearing of foolish playes."
Banquet of Anthony and Cleopatra
by
Jan Steen, ca. 1673-75