|First Appearance||Deadly Ransom|
|Powers||Radiation generation and absorption, radioactive blasts|
Duke Nukem is one of the eco-villains, a radioactive mutant who thrives on radiation and toxic wastes. He's the only villain aside from Zarm and Captain Pollution to have powers of his own in which he generates radiation to fire off radioactive blasts from his hands. He's also dangerously radioactive enough to be considered a walking disaster area, which is why his sidekick, Leadsuit, always wears a radiation-blocking suit of lead when around him.
It is not known, nor is it revealed at any point in the Captain Planet series how Nukem was first mutated, but ever since, he plots to turn the Earth into one giant radioactive zone for him to thrive in as well as turn everyone else in the world into mutants like him.
Duke Nukem is voiced by Dean Stockwell and Maurice LaMarche.
Duke Nukem is a radioactive mutant. He has hard, yellow, scaly skin. He only has three fingers on each hand and two toes on each foot. Nukem is usually found wearing an unbuttoned Hawaiian shirt and a pair of board shorts, as well as a pair of flip-flops. He has a short red mohawk.
Duke's glowing green eyes provide him with x-ray vision. His voice is deep and rather hoarse.
Leadsuit: Leadsuit's name defines his appearance - he wears a full-bodied lead suit in order to withstand the radiation he is exposed to while around Duke Nukem. Leadsuit is timid, rarely arguing with Nukem (and always losing if he objects to anything). Leadsuit is afraid of the dark, and usually gives in at the slightest trouble.
- "What's keeping Skumm!? Fifty thousand nuclear bombs in the world, and all I ask for is one!" (If It's Doomsday This Must Be Belfast)
- The video game character Duke Nukem almost had his name changed because it was identical to this Captain Planet villain.
- Nukem's skin design is similar to Marvel Comic's character The Thing.