Terra is the leader of the Stardroids and one of the main antagonists of Mega Man V. His goal was to power the Dark Star and kill Mega Man.
After the defeat of the first four Stardroids, Terra sends Dark Moon to attack Mega Man and moves to space, where he prepares an attack against Earth while Mega Man succeeds in foiling him. After the death of the second four Stardroids, Terra gets angry that Mega Man had ruined his plans. He fights against Mega Man to make himself worthy again to Dr. Wily, but was defeated.
In Rockman Gigamix
In the manga Rockman Gigamix, the Stardroids are powerful space robots that attack Earth, destroying several robots in the process. To power Dark Moon, he challenges and defeats Mega Man in combat, providing Dark Moon with despair from the people, easily fueling Dark Moon and helping him with his goal. Eventually, a repaired and upgraded Mega Man is able to destroy him, but his own despair and hatred provides the energy to bring forth Sunstar.