OVA
Description
Harka, also known as Haka, is the primary antagonist in the animated short "The Duel." He serves as a military assistant directly under the Covenant High Prophets during the Covenant's early era. Though his specific rank is unspecified, he is a formidable swordsman operating under the Prophets' direct command.

Driven by ambition and loyalty to the Covenant leadership, Haka plots to supplant the Arbiter, Fal 'Chavamee, after Fal renounces Covenant doctrine. Haka sees Fal's heresy as his chance to seize control of their clan and win the Prophets' favor. To provoke Fal, Haka orchestrates the murder of Fal's wife, Han. He manipulates Fal's close ally, Roh, into killing Han by promising this act will protect their clan from the Covenant. Immediately after Han's death, Haka executes Roh to eliminate witnesses, leaving both bodies as a challenge to Fal.

Haka then lures Fal to a duel atop a Forerunner structure, anticipating Covenant forces would block Fal's path. He observes as Fal battles through waves of Unggoy, Kig-Yar, and Mgalekgolo, including three massive Hunters and multiple vehicles. Fal eliminates all opposition.

In their final confrontation, Haka mortally wounds Fal with a slash across the chest. Fal retaliates, impaling Haka with his energy sword. This results in their mutual demise, both warriors dying at each other's hands.

Visually, Haka's design incorporates feudal Japanese influences, featuring armor reminiscent of a samurai. Unlike most Sangheili warriors, he wields a conventional metal blade instead of an energy sword. His appearance and equipment distinguish him within the Covenant forces.

The aftermath of this conflict contributes to the degradation of the Arbiter title's prestige. Following these events, the rank is reserved for Sangheili deemed dishonorable by the Covenant. While the exact dating of these events is inconsistent across sources—some placing it in 2142 CE and others referencing the early Covenant period—Haka's actions remain confined to this single narrative. He has no documented broader appearances or developments in other Halo media.