Dregg is a tall, semi-humanoid, semi-insectoid creature with purple, translucent skin which shows his inner organs. His legs are bent backwards with large, three toed feet and his tail splits into two at it's tip. His arms are covered in spikes and ends in large, clawed hands and his back is adorned by two green wings. His head is diamond-shaped with rounded edges, four yellow eyes, a wide, sharp-toothed mouth, two antennas on top and two mandibles at the edges of his mouth.
In Beyond the Known Universe, the four ninja turtles, Casey and April first encounter him on planet Varanon as he's in the process of selling a very expensive star-spice. After a few unfortunate mishaps with the locals, the gang tries to run away, but accidentally bumps into Dregg on the street and ends up breaking the vial containing his expensive spice. This, along with their clumsy behavior and insults, causes Dregg to try to kill them. Even with their superior numbers, he proves to be a difficult opponent and forces them to leave the planet in haste. Furious, Dregg promises himself to track them down and painfully destroy them.
In The Outlaw Armaggon, Dregg managed to follow the Turtle's movement to the Ice planet they were trapped on in The Moons of Thalos 3, but by the time he reached the ice world the heroes were long gone. While there, Dregg set up a meeting with Armaggon the bounty-hunter. He hired Armaggon to capture the Turtles and bring them to him so he could kill them by himself later on.
He later makes a cameo in the end of Journey Into Mikey's Mind, making a deal with BellyBomb about the turtles and the Black Hole Piece.
In The Cosmic Ocean, Dregg is contacted by Armaggon, with good news. That news being that Armaggon has commandeered the Ulixes, taking the Turtles, April, Casey, and the Fugitoid prisoner and capturing the first piece of the Heart of Darkness. Dregg is very proud of Armaggon, but when he adds on that this will make up for Armaggon's previous screw-ups, Armaggon quadruples his pay, much to Dregg's anger. Later, Dregg and his Vreen drones arrive to rescue Armaggon, who had been captured by Hiidrala and her Daagon, while also demanding the second piece of the Heart of Darkness, threatening to devour Hiidrala and her Daagon to get it. When Hiidrala refuses, a battle ensues. Dregg uses one of his claws to free Armaggon to join the fight, and after managing to overpower Donatello and Leonardo, goes after Hiidrala herself, covering her face with one of his claws, leaving her wide open to a point-blank attack from a missile launched from his chest. However, Leo takes the missile himself, the force of the blast knocking Dregg to the ground, allowing Hiidrala to remove Dregg's claw and then summon her guardian, the Cthugga, which devours Dregg and Armaggon whole. With Dregg gone, his Vreen are unable to act independently of each other and withdraw. Luckily for Dregg and Armaggon, Dregg's ship, the Hornitron, locates the Cthugga's lair and when the Cthugga opens its mouth, the Hornitron launches dozens of Vreen eggs into its mouth, where upon hatching, are able to safely fly Dregg and Armaggon out of the Cthugga. While the Cthugga retreats, Dregg returns to the Hornitron's cockpit, and chuckling evilly, vows that vengeance will be his as he and Armaggon set off to go after the Turtles again.
In The Evil of Dregg, with Armaggon's help, Dregg captures the Turtles' Salamandrian allies, Y’Gythgba and G’Throkka. Using the threat of his forces invading their home planet of Salamandria as leverage, he gets them to betray the Turtles and lure them to his home planet of Sectoid 1 to capture them. After the plan works and Dregg reveals the Salamandrians' betrayal, despite learning from the Turtles that the Black Hole Generator pieces are now in the hands of the Triceratons, Dregg goes to speak to the Salamadrians in private. He double-crosses Mona and Sal Commander, having no intention of calling off his invasion of their home planet. After sending Leo, Raph, Mikey, and Casey to be prey for the Scorpinoid, he reveals in his victory, before being convinced that Armaggon hit him on purpose out of disrespect thanks to April and her psychic powers. The distraction he gives them allows April, Donnie, and the Fugitoid to rescue their allies and escape before Dregg gives pursuit with dozens of Vreen and the Scorpinoid. However, when the Scorpinoid strikes down Mona Lisa, Raph, fueled with fury, attacks Dregg head-on. Dregg is unable to overpower the grief-stricken Turtle, and his head is soon decapitated from his body, revealing a robot one underneath. Despite this revelation, Raph defeats Dregg, and the Ulixes clears out the Vreen and incapacitates the Scorpinoid, allowing the Turtles and their allies to escape Dregg once more.
In The Ever Burning Fire, Dregg manages to follow the Ulixes to the planet Magdomar as he wants revenge on the Turtles for killing the Scorpinoid, referring it as his favorite pet. After losing them again, Dregg teamed up with Mozar and offer him the location of the third piece of the Heart of Darkness, in exchange for the Turtles and 40 million Zemulaks (which he later extends to 100 million when he asks for refuge alongside the money in return for the last piece from Mozar) After getting the final piece and handing it to the Triceratons, Dregg was told that his money would be in a empty room, but as he enters and sees no Zemulaks, it was revealed to be a trap as Dregg is locked in an airlock and Mozar sends Dregg into the freezing outside of space, presumably killing Dregg.
In The Insecta Trifecta, Dregg appears as part of Raphael's hallucinations induced by his fear of bugs while battling Stockman-Fly and his mutant flunkies. Thanks to advice from Master Splinter, Raphael is able to drive Dregg's image out of his mind and save his friends along with defeating Stockman-Fly's mutant lackeys.
Dregg is impulsive and un-accepting of apologies, demanding respect and fear from those around him and is quick to react with violence when offended. This has earned him a fearsome reputation among even the most hardened criminals on planet Varanon, and he appears surprised when the turtles claim they haven't heard of him.
He views insects as superior and is disgusted by the mere thought of physically interacting with other kinds of sentient beings, referring to them as sub-creatures . He is however willing to do business with non-insectoid life-forms, such as Armaggon, if he acknowledge their worth.
Despite him labeling other races as primitive, he has demonstrated anamalistic tendencies himself during combat, such as attempting to eat his opponent.
- This version of him is a lot more insectoid than his 1987 counterpart.
- Dregg's name is derived from the English word "dreg". This term refers to dirt and evil people.
- Lord Dregg in this series appears to take aspects of Maligna, the insectoid Queen of the malignoids who was an enemy of the Mighty Mutanimals in the Archie comics.
- Lord Dregg's hands slightly resemble the character Spider Bytez (2012 TV series).