Rick And Morty: 10 Most Dangerous Villains
3. Hoovy's Descendants
This is the second villain (technically in this case it's a group of villains) to appear from "Rick Dinner Mort Andre," so that should tell you something about the quality of the episode.
In the very same episode to feature Mr. Nimbus, he who controls the oceans and the police, we encounter Hoovy. A simple farmer in a Narnia-esque dimension Rick uses to stash, and age, his win, Hoovy himself isn't the bad guy. His descendants, however, are another matter.
Time runs differently in Hoovy's dimension, which is why Rick ages his wine there. When Morty is tasked with retrieving a case while Rick dines with Mr. Nimbus, Hoovy helps him carry it into Morty's world. When Hoovy returns home, so much time has passed that his beloved wife is dead, and his son, Japheth is now grown - and resents his father for having abandoned the family.
With his dying breath, Hoovy names Morty as the scourge behind his disappearance (hey, maybe he is a villain), leading to generation after generation of his descendants preparing for Morty's return - and their revenge. The speed of time in Hoovy's world leads them to quickly go from a medieval society to an advanced technological one, a world that even Rick cannot defeat when he's inevitably drawn into it. It's actually Mr. Nimbus, not Rick, who saves the day.