Evil Morty (also known as "Eye Patch Morty") is the show's most calculated and successful antagonist. Unlike Rick Prime, who was born a monster, Evil Morty is a product of being "pushed too far" by the Rick-centric multiverse. He is the only character who didn't just want to kill Rick—he wanted to leave him behind.
Key highlights of his cold, calculated lore:
The Puppet Master: He first appeared in Season 1, using a "dummy" Rick controlled by a transmitter hidden under his eye patch to frame C-137 for the murder of other Ricks. He kidnapped hundreds of Mortys to create a "human shield" of pain to hide his base.
The Politician: In the Season 3 episode "The Ricklantis Mixup," he ran for President of the Citadel of Ricks. Despite being an "inferior" Morty, he won by appealing to the disgruntled working-class Ricks and Mortys, then immediately executed the Shadow Council to become a dictator.
Breaking the Curve: His ultimate goal wasn't power, but freedom. In the Season 5 finale, he revealed that Rick had walled off the Central Finite Curve (the portion of the multiverse where Rick is always the smartest). Evil Morty hacked the Citadel’s systems, slaughtered thousands to fuel his ship, and literally "punched a hole" through the multiverse to reach the "Yellow Portal" space where Rick is not a god.
The Reluctant Ally: In Season 7, we see him living a peaceful, "Rick-free" life in the outer multiverse. He only returns because Rick C-137’s search for Rick Prime is "glitching" the multiverse. He eventually helps Rick kill Rick Prime—not out of love, but because Rick Prime was a "disorderly" threat to his peace.
His Philosophy: He views the relationship between Rick and Morty as a cycle of abuse. He believes every Rick is a "drug" and every Morty is an "addict." By leaving, he proved that a Morty can be smarter, more ruthless, and more independent than any Rick.
He is currently back in his own private dimension, armed with the Omega Device (a weapon that can erase someone from every timeline), making him the most powerful being in the show—he just wants to be left alone to enjoy his drink.