MCU: What Happened To Everyone Who Held The Mind Stone?
6. Ultron
Ultron was born from the Mind Stone via the manipulation of the energy and the decrypted code within accompanied by Tony Stark's program, J.A.R.V.I.S., that resulted in the creation of the program that would become Ultron. When he first came into being, he subdued J.A.R.V.I.S. and downloaded himself onto the Internet.
At this point in the film, Ultron wasn't in possession of the actual Mind Stone itself, but that would come later. He engaged in numerous fights with the Avengers and even got the aid of Wanda and Pietro Maximoff, but they would later betray him when his true goal was revealed.
Ultron later recovered the Mind Stone, which he separated from the blue housing it was kept inside of at the tip of the Scepter. This was the first time the Mind Stone was revealed as it truly was at any point in the MCU.
Ultron planned to have the Mind Stone embedded in the forehead of a new body he built for himself, but thanks to team's mission that recovered that body as it was being completed, and Thor's quick use of lightning, Ultron never made it into his new form. In his place, the Mind Stone was joined with J.A.R.V.I.S. and bits of Ultron's code to become the superhero known as Vision, who would be the next person to wield the Mind Stone.