The Robot is the main antagonist of "Robot Rabbit".
Elmer Fudd is shown as a carrot farmer who is happily going about his chores singing "In a Little Red Barn (On a Farm down in Indiana)". Halfway through the song, he realizes Bugs has joined his singing. At the end of the chorus of the song, Bugs dives into his hole, and carrots fly into the air. Elmer angrily laments "Ooooh, da wascal wabbit is in my cawwots again!", and then rushes into his house to retrieve a shotgun. After shooting into an empty hole (Bugs had conveniently left the hole, then does his "fake dying" act), Elmer exclaims "Howway! Da wabbit kicked da bucket!", then he and Bugs start dancing as a result until Elmer begins to realize Bugs is still very much alive.
That prompts Fudd to call "ACME Pest Control": ("Hewwo? ACME Pest Contwol? Weww, I've got a pest I want contwolled.") for a robot with the express purpose of evicting Bugs. The robot initially confuses a mule and Elmer — who was trying to explain to the robot what a rabbit looks like — for his intended target before getting the early upper-hand. Bugs quickly evens the score by luring his antagonist under a rotating water sprinkler, causing the robot to rust. Elmer however resolves this setback just as quickly by oiling the robot up and then warns him that he'll be sold for old scrap iron if he doesn't get the job done.
Later, Bugs disguises himself as a female robot (where he literally throws a wrench into their "relationship"), before finally causing the robot to follow him through a construction site and beneath a pile driver. Back at home, Elmer starts wondering how the robot fared, Bugs greets him and dumps the remains of the robot onto the floor; it prooved that the robot was crushed underneath the pile driver. As Bugs walks off, he comments to himself: "Ya know, someday, dese scientists are gonna invent something dat will "outsmart" a rabbit".