DarkWarrior Duck was a twisted dictator version of Darkwing Duck who appeared only in the episode "Time and Punishment".
DarkWarrior Duck wears a much more threatening looking costume than his former Darkwing persona. He still has his signiture hat, and cape, but now wears a (jump-suit like) purple costume with a dark belt, dark boots, large black gloves and heavy, spiky armor over his shoulders. His belt has a satchel on it for his former gas gun.
His entrance smoke is now red, instead of his normal blue smoke. His mask is also black now, and when he wears it his eyes glow red. Though this seems less like some form of technology and more of a way to visualize his insanity, since his eyes are normal the first time he sees Gosalyn even with the mask on. Like his past-heroic counterpart, he was voice-portrayed by Jim Cummings.
Weapons and Gadgets
DarkWarrior has a legion of flying robots at his disposal, a large tank (presumably in place of the Ratcatcher), the Thunderwing (loaded with guns and missles), and his former gas gun (now a handheld missle launcher).
Even though DarkWarrior doesn't deem himself as evil and probably had good intentions, he had strayed from the path of justice and became an extremely dark anti-hero. He wholeheartedly believes in the use of lethal force, does not give criminals a trial, and is liberal with giving out the death penelty. A sharp contrast to Darkwing's non-lethal style. DarkWarrior also sees every crime equally as heinous, right down to tearing off the 'do not remove under penalty of law' tag on pillows.
Time and Punishment
After Gosalyn accidentally got sent to the future in Quackerjack's time top with him and Megavolt inside, Darkwing had spiraled into depression, believing that she had ran away. When he sees a child that resembled Gosalyn in need, Darkwing decided to fight crime again, but this time with a much darker side. He ruled St. Canard with an iron fist (something the Fearsome Five has never done) and sent minor offenders to the electric chair instead of arresting them. He has even fired his sidekick, Launchpad McQuack, for disagreeing with his new doctrine. With Launchpad, Gosalyn had defaced a statue of DarkWarrior to get his attention. Immediately, DarkWarrior fired a missile toward them but stopped it when he saw Gosalyn.
He welcomed back Gosalyn with loving affection and arrested Launchpad, believing he put her up to vandalizing his statue. He decided to make Gosalyn his new sidekick, but arrested her when she disagreed with his doctrine and wanted to go back to the past so that DarkWarrior never existed. With Quackerjack's time top, DarkWarrior thought about going back in time and rewriting history to his iron fisted image. Gosalyn had escaped with Quackerjack, Megavolt, Launchpad, and everyone else DarkWarrior had arrested only for DarkWarrior to pull out his gas gun at her that he had turned into a missile launcher. He even declared that all her past misbehaviors meant that she was a bad egg from the start. He hesitated and stopped at the last second before Launchpad knocked him out, giving Gosalyn, Megavolt, and Quackerjack to go back to the past and set things right.
Though Gosalyn returned home and it is assumed that the time line DarkWarrior was from now never existed he was meant to be brought back in season 4 before the show was cancelled. Thus it can be implied DarkWarrior now exists in an alternate timeline, much like how Negaduck existed in an alternate universe.
Crisis on Infinite Darkwings
Darkwarrior Duck was one of the alternate Darkwings that were brought to St. Canard by Negaduck and Magica De Spell. He announced to the city that the War of Darkwings had begun and pointed his tank's barrel at Darkwing, but Morgana teleported him back to his house before Darkwarrior could fire. Later, when Quiverwing Duck was subduing the mind-controlled Darkwings, he ran into Darkwarrior, who had captured Professor Moliarty and Tuskernini.
Darkwarrior said Magica didn't have to hypnotize him, which is odd since Darkwarrior believes that what he is doing is good. Quiverwing took out the two robots Darkwarrior had with him and then destroyed his tank by plugging up the barrel with a cork arrow. Darkwarrior told Quiverwing not to bother with him and to help Darkwing, before he lost Gosalyn. He was presumably returned to his home dimension with the other Darkwings.