Darkonda kidnapped a little girl in the past to have her brainwashed and raised to become the evil Astronema. A vile, ruthless soldier of darkness, Darkonda displays no care for innocent lives and revels in causing pain to his foes. In a series with honorable antagonists, Darkonda is set apart by making loyalty solely to himself and backstabbing everyone into a borderline religion. He tries to murder his noble ally Ecliptor, and occasionally forces Ecliptor to merge with him against his will before overwriting his mind to serve the forces of darkness as a brainwashed soldier. Darkonda attempts to outright murder the overlord of the forces of darkness, Dark Specter, at points when it might even screw over his own side.
Deviot, in a show full of villains with standards, had none. He was a manipulative, treacherous Starscream who would cheerfully throwaway his men's lives, thought brainwashing was a useful tool, and had no loyalty to anyone. When Scorpius wouldn't allow him to enter the cocoon, Deviot arranged for his death. When Trakeena, and not he, inherited control of the army, he sends two of his men to kill her; when she survives the assassination attempt, he kills the assassins to cover his tracks. He later brainwashed Loyax into fighting the Rangers, leading to his death as well. When Trakeena finally does enter the cocoon, Deviot ambushes her, and fuses with her. The absorption of his evil soul drives Trakeena completely over the edge, leading her to murder her mentor, Villimax, use her men as suicide bombers, and try to regain her human form by stealing the Life Energy of others. Totally untrustworthy, and out only for himself, Deviot proved that on his own, or influencing Trakeena, he could do more damage than any other villain in Lost Galaxy.
Queen Bansheera is probably the worst boss in the history of the entire franchise. The queen of the demons, Bansheera returns to power by callously sucking the life out of one and forces Diabolico, her once loyal general, to open fire on his enemies without caring her most loyal minion Loki, whose only desire has ever been to serve her, is caught in the blast and dies. Diabolico has his mind forcibly erased to serve as her pawn. Her own son, Olympius fares little better, and Bansheera once ordered him abandoned to his fate while laughing. He is forced to fight alongside a brainwashed Diabolico, and his death provokes no feeling in her whatsoever. In addition, Bansheera attempts to open a gateway to the demon realm, allowing all demon-kind to pour out and overwhelm humanity.
Venjix is a sentient computer virus who, after being unleashed on the world's computers, proceeds to exterminate almost the whole of the human race. When the last elements of humanity hole up in the domed city of Corinth, Venjix makes repeated attempts to destroy the city in order to wipe out what is left of humankind. To achieve those ends he: enslaves people to work in his factories, brainwashes Dillon's sister into becoming Tenaya 7, brutalizes his minions if they question his orders, discards any henchmen he no longer needs, and mentally hijacks half the city in order to force them into compliance with his orders. Possessed of no good qualities, and with the highest body count in the history of the franchise, Venjix is among the worst that Power Rangers has to offer.