D-Fekt is a mining robot built by Dr. Eggman and the main antagonist of the 2016 3DS game, Sonic Boom: Fire & Ice.
Dr. Eggman built D-Fekt to locate a new element discovered called Ragnium via magnetism to energize his robots. However, D-Fekt ends up malfunctioning and magnetizes anything but Ragnium. After Eggman disposes D-Fekt to find Ragnium on his own, D-Fekt learns to use his powers to his advantage and now seeks to defeat Sonic the Hedgehog to win back Eggman's appreciation.
Sonic Boom: Fire & Ice
D-Fekt first appears when Sonic and Amy discover the first fire and ice fissure in the Kodiak Frontier. He attempts to stop the two, but fails when Sonic jumps out of the way. He then angrily storms off to create the first boss, Unga Bunga. After Unga Bunga, is defeated, Sonic, Amy, and Tails chase after D-Fekt, only for him to be captured by Dr. Eggman, who orders him to do one job: protect the remaining fissures from being closed by Sonic and friends. He then throws him off into the distance to get back to work.
In the second area, Seaside Island, D-Fekt is cornered by Sticks the Badger, who is infatuated by his "adorable" design and believes it to be love. Because of Sticks' distraction, Sonic, Amy, and Tails succeed in closing the second fissure. D-Fekt rushes off to the Paleo Tarpits while Team Sonic argues with Sticks over D-Fekt's (or Ador-O-Bot 2000 as Sticks refers him) destructive personality.
In the Paleo Tarpits, Sonic and Tails find the third fissure and close it. D-Fekt attempts to use his magnetism to re-activate the fissure, but it is once again closed by Sonic and Tails and D-Fekt falls into a puddle of tar, creating the second boss, Sticky Situation. After Sticky Situation is defeated and D-Fekt runs off to protect the remaining fissures, Sonic and his friends question why D-Fekt is so desperate to keep the fissures open.
After Sonic and his pals close the fissure in Cutthroat Cove, Tails learns that the fissures leak out Ragnium radiation that D-Fekt is covered with. After being caught up by Sonic and the gang, D-Fekt remembers when Eggman first created him and was disgusted by his reversed magnetism, calling him D-Fekt instead of his regular name of RagnaBot. D-Fekt jumps into a pile of rocks and creates the third boss, Creepy Crawly, which Sonic and Knuckles defeat.
In Gothic Gardens, Sonic and his friends succeed in capturing D-Fekt, but Sticks lets him go because she thought he was scared. When they do find him resting in the graveyard, Tails uses Sticks to place a tracking device on him so they can track where the Ragnium source is coming from.
Sonic, Tails, Knuckles, Amy, and Sticks follow D-Fekt to discover a mine in Ragna Rock, where Eggman is harvesting Ragnium from within the Earth. Eggman scolds D-Fekt for failing to protect the fissures and kicks him around, saying D-Fekt was not a worthy name for him. When Sonic and his friends arrive to confront Eggman, D-Fekt, having enough of Eggman's abuse, magnetizes the entire mine together to create Double Trouble, the final boss of Sonic Boom: Fire & Ice. After Sonic and Sticks defeat the mechanical beast made of fire and ice, Eggman digs up D-Fekt from the rubble of the destroyed mine and apologizes for mistreating him and gives him to Sticks as a present for helping him, before Tails removes his magnetizing ability to make him permanently harmless.
D-Fekt is an orange robot with three magnets located on his head. He has yellow hands with four gray fingers on each. He has a gray face with blue LED eyes and a mouth, making him look similar to Orbot and Cubot. Despite having a mouth, D-Fekt is mute and only speaks through robotic grumbles.
- D-Fekt's name is a play on the word "Defect," which is a reference to his defect that occurred upon his activation.