Krombopulos Michael

Krombopulos Michael was a Gromflomite assassin that purchased weapons from Rick Sanchez. His final purchase was an anti-matter handgun, used to kill a gaseous target that couldn't be destroyed with normal weapons.

After breaking into the facility used to hold his target, he was crushed to death by Morty after falling asleep while piloting his grandfather's spaceship. Though as there are infinite universe in the shows cannon it is very unlikely he isn't alive in at least one other universe.

Prior to his death, Krombopulos customarily handed out business cards that indicated his occupation, location, Twitter and Facebook accounts, and the hashtag #KMichaelKills.

Trivia
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 * Many aspects of Krombopulos Michael resemble the Rodian bounty hunter Greedo from the Star Wars franchise, such as his antennae, mouth, insect-like eyes, green skin, and Mohawk.
 * At the beginning of the episode in which Krombopulos Michael dies, we see Rick claim an identification number when dropping Jerry off at an inter-dimensional day care: 5126. At the end of the episode, we see that the Rick and Morty being followed throughout the episode had incorrectly picked up Jerry 5126. As a result, some fans theorize that the events of the episode followed a Rick other than that of the replacement dimension, and thus the Krombopulos Michael of the universe throughout the main canon is still alive, and may appear again in a future episode.