TV-Series
Description
Commander Cossack, also known by his self-given nickname "Cossack the Terrible," is a character who appears in the American-produced third season of Voltron: Defender of the Universe. He is a Drule from Planet Doom, a humanoid race typically characterized by pointed ears, yellow eyes without visible pupils, and a lack of eyebrows. Cossack stands roughly the same height as Prince Lotor but is shorter than King Zarkon. He has long, unkempt brownish-grey hair, though he is almost never seen without his signature horned Doom helmet and flowing yellow cape. Only in the final episode of the season and a deleted scene does he appear without his helmet.

Cossack is introduced into the ranks of Doom's forces as a replacement for a previous commander, Mogor, who was eliminated by Prince Lotor. His personality is a blend of boisterous bravado and underlying cowardice. He is something of a slacker and a joker, often complaining about his lot or making sarcastic quips, but this lightheartedness is paired with a cruelty that matches his predecessors. He favors using a whip as his primary weapon, employing it in combat as well as for tormenting slaves and captives. Despite his loud and confident demeanor, Cossack's courage frequently fails him when a battle turns against his favor, and he is quick to retreat from a superior foe, such as when he fled from Planet Pollux upon sensing the approach of the Voltron Lions.

His primary motivation appears to be a desire for advancement and glory within the Drule Empire. He eagerly seizes opportunities to lead attacks, such as the raid on Planet Pollux while Zarkon and Lotor are recovering, hoping to make a name for himself. However, his ambitions are often tempered by a strong sense of self-preservation and a tendency to shirk difficult work. While he can be as treacherous as any of Doom's commanders, he is also frequently depicted as something of an underdog or a "punching bag" for the universe, a position he openly laments.

In the story, Cossack serves as an envoy and field commander, undertaking missions directly for Prince Lotor and King Zarkon. His schemes include leading attacks on planets like Pollux and Oron, deploying Ultra Droids, and attempting to steal the Yellow Lion. He works closely with the witch Haggar, with whom he shares a bond of dark humor; on one occasion, he jokes about kissing her if they win a battle, only to immediately retract the statement. He shows deference and a degree of fear toward Prince Lotor, being wary of the prince's wrath. His relationship with Haggar is pragmatic, and they often find common ground in their annoyance or scheming, such as when they conspire to undermine the newly arrived Queen Merla. When Merla begins to rise in power, Cossack is openly resentful and complains to Haggar about her behavior, though he lacks the nerve to confront Merla directly.

His character does not undergo significant development, remaining a consistent antagonist throughout his appearances. He is introduced as a promising new threat but has been critically described as becoming a "sniveling whiner" who ultimately adds little to the series in the long run. He maintains his role as a scheming but often incompetent commander, whose plans are consistently thwarted by the Voltron Force.

In terms of notable abilities, Cossack is a capable pilot and ground commander, leading armadas and ground assaults. His skill with a whip makes him a dangerous opponent at close range, and he is proficient in the use of Doom's robotic technology and weaponry. However, his most defining trait is not a combat ability but his comedic and occasional cowardly nature, which sets him apart from the more regal but sinister Prince Lotor and the imposing King Zarkon.