Superman #229

Superman #229 (On Sale: June 18, 1970) has a cover by Curt Swan and Murphy Anderson.

We begin with  "The Ex-Superman" by Leo Dorfman, Curt Swan and Joe Giella. Continuing from the previous issue, Superman, suffering from power-loss, is rocketed to Morgu, the executioner's planet, by the Anti-Superman Gang. 

While there, he evades the planet's executioners and finds his way to a group of people who serve as slaves on this world. The are led by a man named Supro who wears a costume similar to Superman's. Supro attacks Superman, but the Man of Steel wins the fight and becomes the leader. He is given the Supro costume.

When the girl Lirlon comes into the slave camp, Superman tries to protect her. Lord Korpon wants to execute her and has guards drag her away. Superman follows, but he believes he was too late to prevent her death. Instead he meets Supergirl, who was disguised as Lirlon. Supergirl explains that she retrieved Superman's costume from criminals on Earth and found red dust on it which caused Superman's power loss. With the costume cleaned, Superman slowly regains his powers and returns to Earth.

Superman also learns that the slaves came from Earth. He had gone back in time to save the people from a sinking continent. They fled into space and were eventually enslaved. Over the centuries, their honoring of Superman turned into Supro, their hero.

We end with "Clark Kent, Assassin" by Leo Dorfman and Wayne Boring. When Perry White receives an award honoring him for 25 years of service to the Daily Planet, his friends and colleagues each sign the plaque. A short time later, Clark Kent goes berserk and tries to kill Perry. As Superman he has no memory of his actions, but each time he becomes Clark, he tries to kill Perry again. 

Eventually Superman discovers that a Kryptonian artifact has made him sleepwalk. Clark's real target was not Perry himself, but the signed plaque hanging on the wall. Clark subconsciously realized that his signature and Superman's were close together on the plaque, and the handwriting was the same. To protect his secret, Clark destroyed the plaque. He then tries to explain his actions as having been hypnotized by a criminal. I'm not going to say Dorfman was out of ideas, but two stories in a row where some red kryptonite-like substance was the culprit? Really?

Edited by Mort Weisinger.