Dark Mind is an evil deity who is the final boss of Kirby and the Amazing Mirror. He wants to conquer the Mirror World and when Meta Knight realizes that it will threaten Dream Land, he tries to put a stop to it. At the end of the game Kirby fights Dark Mind using Meta Knight's sword.In Team Kirby Clash Deluxe an entity named King D-Mind is implied to be Shadow Dedede possessed by Dark Mind, but it is never said clearly if it is truely the case.
Dark Mind act as the true Final boss and antagonist of Amazing Mirror, he is also the master of Dark Meta Knight. According to the description of the piece of armor called the Dark Mind Helmet, Dark Mind soul was shattered by the Galaxia during his fight with Kirby.
King D-Mind, the entity who is commanding Dark Taranza is wearing the same helmet as Dark Mind and house his giant flaming eyeball inside of his body.
Additionally, the same Helmet can be bought at the Shoppe and be equipped by the Hammer Lord
In Game description
Team Kirby Clash Deluxe
Dark Mind Helmet description
Armor that once belonged to one who schemed to rule the Mirror World. It is said his soul shattered at the flash of a blade.