Medea Pideth Machina

Medea Pideth Machina is the central antagonist of the Rising of Shield Hero. Medea is a goddess whose goal is to unite the eight worlds which comprise the Heroes World, which have been reduced to two or four by the time the story takes place, and then descend into the fused world to devour its energy and move on, presumably to do the same thing again elsewhere.

Much like her fragments which work to sabotage the heroes and ensure her Waves of World Fusion go uninterrupted, Medea is rotten, selfish and unrepentant, Malty Melromarc herself is nothing more than a fragment of Medea and as such Medea possesses all of her memories and personality traits, only she is far worse than Malty because she has the power to back up her selfishness.Basking in luxury, moving the world to her pleasure, thinking of men as nothing more than tools to be used, an aura conveying these feelings emanated from her.

She sees everything existing for her sake and inflicts betrayal purely because she loves the expression on her victim's face when their friends and family are turned against them. Similar to Malty she also immediately starts acting like she's the victim when her enemies start getting the upper hand, complaining as she's killed that so many people want her dead. She also grossly overreacts to light wounds, annihilating Ren and Motoyasu for inflicting a light cut on her wrist, it's likely she's simply not used to getting hurt at all.

Her grudge against Naofumi is personal to the extreme, after killing Motoyasu and Ren, she proceeded to erase Naofumi from the world and every divergent world and parallel timeline he ever existed in, as Ark put it, "She really, REALLY, wanted you dead man", and she was even more annoyed when he came back even from that, this time a God himself, and completely turned the tables on her.

She spared the Heroes' world for a time only because it amused her to have her underlings kill the world's inhabitants in a twisted war game, she also personally interfered whenever it looked like her army was losing, referring to it as her correcting the enemy's side's cheating. When Naofumi returned and completely turned the tables on her by giving the Heroes' side a god, she immediately tortured her subordinates to death just to laugh at their cries of betrayal before confronting the heroes herself, which even disgusted the heroes, who themselves had no sympathy for her men.

She is extremely boastful, calling her attacks with words like "ultimate", "infinite", "Faster than infinity" ect, but as Naofumi himself states when he becomes a god, it's all bullshit, her attacks are bound by finite restrictions, it's just that she's so powerful that non-gods normally wouldn't be able to notice.