It is not very clear.
Morty mutates Ethan with the Morphizer-XE
We do not actually see this until after the credits; the Rick and Morty Wikia summarise the scene quite well:
In a post-credits scene, a mutated Ethan is seen walking home, presumably by Morty for hurting Summer and as a lesson in shallowness. The three tech support aliens spot him, but decide not to help due to their newfound freedom. Their relief turns to horror, however, when one is carried away by an eagle.
The scene focuses on the three tech support aliens that Beth released from the Morphizer-XE, but we can see a mutant Ethan slowly making his way along the highway, above.