Strange Tales #127 (1964)
Dictatorship ruled by Dormammu
The Mindless Ones have a normal human appearance, with exceptions of them having only one yellow eye in the center of their heads and no visible ears. They stand at an average height of 7' tall, They have an average weight of 900 pounds, no hair and Grayish-brown rock like skin.
When the earth mystic Doctor Strange first visited the Dark Dimension to confront Dormammu, Dormammu's niece Clea warned Strange of the threat that the Mindless Ones posed. Strange went ahead to combat Dormammu, but during their clash, Dormammu's power waned, and the barrier holding the Mindless Ones fell. Dr. Strange helped Dormammu hold the creatures back until the barrier could be raised again, and Dormammu established an uneasy truce with Earth. When Dormammu forsook this truce in order to grant Baron Mordo the power needed to defeat Dr. Strange, Clea came to Strange's defense by lowering the the barrier with a mystic device, forcing Dormammu to remake the barrier. When Strange and Dormammu finally faced each other in the Dark Dimension, Dormammu mystically caused the Mindless Ones to sleep so that he could use his full power, however, Dormammu was bested. When Dormammu later disappeared after assaulting the cosmic being Eternity, the barrier was temporarily lowered, but Umar emerged from retirement to seal the barrier. Umar tried to destroy Dr. Strange by casting an illusion on one of the Mindless Ones to make it seem to be Clea, tricking Strange into setting "Clea" free, but ultimately evade the creature. During her rule of the Dark Dimension, Umar would execute her enemies by sending them through the barrier into the Mindless Ones clutches.
Clea eventually led a rebellion against Umar's rule; the rebels operated out of the Mindless Ones domain, one of the few locations in the Dark Dimension which Umar's servants feared to enter. As Dr. Strange aided Clea's rebellion, Umar lowered the barrier to increase her might, releasing the Mindless Ones, but Dr. Strange and the Outcasts (former sorcerers of King Olnar once known as the Mhuruuks) drove the creatures back until they could be contained. Dormammu later regained mastery of the Dark Dimension and has repeatedly employed the Mindless Ones as his minions, using magic to make them follow orders and refrain from attacking him. Under Dormammu's control, they have been dispatched against Clea's rebellion and other such foes such as the Defenders, Avengers, Darkhawk, Fantastic Four, Spider-Man (Peter Parker) and the Archenemy.
The Mindless ones once managed to open a vortex and cross the border into Times Square, in New York. Many of Earths heroes, including Spider-Man, Thor, Cyclops of the X-Men, Iron Man, and the Fantastic Four gathered to put a stop to the Mindless Ones spreading their damage through to the rest of New York. In an attempt to return the Mindless Ones to there own dimension the heroes used a device created by Reed Richards to funnel their powers through every vibrational plane until it fond the right one which matched the Faltine dimension of the Mindless Ones. Once found, it overloaded and caused the vortex to collapse, thus creating a kind of vibratory echo that pulled back everyone who came through it.
The heroes (Though some reluctantly) agreed and went ahead with their plan only to learn that they had been tricked. Dormammu (who's essence had been cast into a dozen dimension by Doctor Strange) had commanded his minions to arrange an attack on New York, which caused its heroes to bring such dire energies to bear. In such a way as to pull that which was lost across the dark dimensions, attracting them all to one place. In doing so would bring the essence of Dormammu from its scattered domains so that they would rejoin and become one, and Dormammu would live once more. While the rest of the heroes battled the Mindless Ones, Doctor Strange engaged Dormammu in an exchange of mystic force.
When Spider-Man accidentally entered the fray his presence changed the dynamics of a spell directed at Dormammu and resulted in Spider-Man and Doctor Strange being cast outside time and space. The two traveled through a randomly jumping time-line until Doctor Strange could send Spider-Man forward in time to warn the heroes of Dormammu's return. Trusting Spider-Man's warning the heroes agree to wait before using Reed Richards device against the Mindless Ones. After twenty minutes Doctor Strange arrived and collapsed the vortex of the Mindless Ones, Drawing them back to their home dimension, (all the while unaware of his adventure with Spider-Man).The Mindless have also been used as minions by other mystical beings, including the Asgardian sorceress Karnilla, who employed one to drive away Loki; Yandroth, who dispatched a number of them to attack Atlantis; and Doctor Doom, who mastered them using them arcane power from the Haazareth Three demon trio, pitting them against the Thing. One of the Mindless Ones wound up in the possession of the mad collector Doctor Midas, who used it against his own daughter Exterminatrix and Marvel Boy (Noh-Varr). The demon Nightmare has used Mindless Ones to assault the Ghost Rider (Johnny Blaze) and to populate his "Nightmare Island", disguising the creatures as various monsters and individuals taken from the minds of the humans who visited the island, including the Hulk, Fin Fang Foom and many of the Mole Man's mutates. The Mindless Ones were most recently employed by Rorkannu, a lesser member of the Faltine who was hired by the Beyond Corporation to attack Shotcreek, Colorado. Rorkannu hoped to eradicate humanity and repopulate the Earth with the Mindless Ones, but he was ultimately defeated by the Nextwave team's Captain, halting the Mindless Ones' invasion.