The Cobra Troopers are shown as original infantry soldiers equipped with conventional military gear (as opposed to the more hi-tech accouterments of the later Vipers). They were prominently featured on both the cartoon and comic series, and depicted as unintelligent and slightly cowardly.
The Cobra Troopers were the foot soldiers of Cobra in the series, serving as cannon fodder similar to B.A.T.S.. They were used as common infantry for the remainder of the entire series, even during the film G.I. Joe: The Movie. However, in the DiC series, several Cobra Troopers who were loyal to Cobra Commander reformatted themselves as Python Patrol and Cobra-Vipers in his attempts to conquer the world.
G.I. Joe: Resolute
In the miniseries, the Cobra Troopers are shown wearing both red and blue military uniforms, as they are assigned in assisting Cobra Commander in his plot to recover COBRA's finanical investments by taking control of the world's country resources. They are mostly seen during Cobra Commander's speech when he lectures them about the betrayal of Major Bludd, in an attempt to assert his control over them so that they wouldn't betray him.
G.I. Joe: Renegades
In the series, the Cobra Troopers are depicted as security guards for Cobra Pharmaceuticals, right before the entire facility was destroyed. This event is what led the Joes to be framed for the destruction and to be branded as fugitives of the law, all part of Cobra Commander's plan to covert COBRA's true activities from the world.
In the film series, the Cobra Troopers are seen in black and white military uniforms, but are far more ruthless than ever. They are also involved in Cobra Commander's true plan to take over the world by utilizing a satellite system that involves dropping giant tungsten rods into major capitals, which would result worldwide destruction unless all countries surrendered to Cobra Commander.
G.I. Joe: Renegades
G.I. Joe: Retaliation