Who is the heir of Julius Caesar and also who joins mark Antony?

The heir of Julius Caesar is Gaius Octavius, commonly known as Octavian, who later became Augustus, the first Roman Emperor. After Caesar's assassination, Octavian formed an alliance with Mark Antony, initially joining forces to defeat their common enemies, including the assassins of Caesar. Their alliance, however, eventually deteriorated, leading to a power struggle between them.