The Jedi Killer is a drawing of a three-barrelled gun that is intended to kill Jedi from Star Wars.
The gun is a drawing by Kmlkmljkl, a YouTuber who posts comedic clips.
He posted an MS Paint drawing of the gun on Reddit and got over 1.7k upvotes.
Jedi is a fictional organization of characters in the Star Wars universe who are highly skilled warriors.
They have the mystical power of the Force, which includes telekinesis and mind control.
Jedi have lightsabers, which are powered by Kyber Crystals and can cut through nearly everything.

The original drawing contains a tripe-barreled gun named the “Jedi Killer”.
The Jedi in the drawing has a green light saber that deflected two bullets, but the third one hit him.
After the original drawing was posted, many users started making parodies of it.
Some users added more barrels to the gun while others added attachments.

A user (Johnmarmalade on Reddit) drew one more lightsaber on the Jedi, which deflected the third bullet.
In addition, he canceled the word “Killer” from “Jedi Killer”.
Other users made drawings of the Jedi countering the gun.
However, most users made the gun more powerful.

A user (Al2theE_X on Reddit), added more barrels to the gun in the drawing.
This countered the Jedi’s second lightsaber because the other two bullets hit him.
He named the drawing “Jedi Killer 2.0”, which is an upgraded version of the gun.
The post got over 18k upvotes on Reddit.
Other edits of the drawing include the same gun, but with multiple barrels shaped like a stickman, the same gun with missiles, and the same drawing, but with an FN P90.
This meme is categorized as an “Exploitable meme” because people can easily make edits to it.
Further reading
What Does “Please Do Not the Cat” Mean?