Egba Atler commands the Southern Cross Corps, an elite Principality of Zeon mobile suit unit once led by the deserter Cucuruz Doan. He intensely hates Doan, perceiving his desertion as a deep betrayal. This animosity drives Egba to physically attack subordinate Danan Rashica for merely uttering Doan's name, explicitly forbidding any mention of the "traitor." His leadership is aggressive and fiercely loyal to Zeon's cause, with zero tolerance for disloyalty.

The Southern Cross Corps utilizes advanced MS-06GD Zaku High Mobility Surface Type mobile suits, boasting enhanced ground mobility and weaponry like anti-ship rifles. Egba pilots a custom unit featuring a spiked shoulder shield and a machine gun equipped with a bayonet. Under his command, the unit executes high-efficiency combat, decisively defeating Federation GM units and rescuing allies during the battle at Casablanca.

Egba demonstrates significant combat prowess, showing confidence against formidable foes like the RX-78-02 Gundam. During a mission to Alegranza Island—ordered by General M'Quve to investigate malfunctioning nuclear missiles—Egba leads the Southern Cross against Federation forces and Doan. He personally disables Doan's Zaku II in combat, disarming it and mocking Doan's efforts. However, Amuro Ray intervenes in the Gundam, engaging Egba in a duel. Exploiting the cliffside terrain, Amuro destabilizes Egba's mobile suit and slices it in half with beam sabers. Egba dies as his unit plummets and explodes.

The exact nature of Egba's history with Doan remains ambiguous. While his vitriol suggests ideological outrage over the desertion, some interpretations suggest an unresolved personal rivalry or feelings of inadequacy relative to Doan's legendary piloting skills. His relentless drive to eliminate Doan ultimately fuels his actions during the Alegranza operation.