The Black Gears (in Japanese: 黒い歯車 Kuroi Haguruma) are flying, mechanical dark gears of varying size with DigiCode symbols inscribed on them that are the villainous tools in Digimon Adventure 01. Those mind control devices are used by the sinister Champion Level Digimon Devimon to create his own minions in his war against the DigiDestined by twisting good Digimon as other Digimon (evil or neutral) into evil as well as often sending them into an angry, berserker rage.