Psi is a DC character created by Paul Kupperberg and Carmine Infantino for Daring New Adventures of Supergirl #1 November 1982.
Born in Chicago, Gayle Marsh had a fairly normal and undistinguished childhood. At the age of 12, however, the child began to display the signs of extraordinary psychic power. Her parents were frightened by the powers that Gayle was displaying and so they consulted the family doctor. He recommended that Gayle be turned over to the more experienced hands at the Institute of Higher Psychokinetic Study, a Chicago based research facility specializing in the study of such extra sensory phenomena.
The researchers at the institute were excited at the prospect of examining Gayle, finding her telekinetic powers to be some of the most powerful ever recorded. One researcher, Daniel Penderghast, seemed to find Gayle's powers particularly fascinating and a friendship quickly developed between him and his young subject.
Initially Gayle was only meant to be at the Institute for a week of so, but during her stay there, her parents were killed in a road accident. As Gayle had no other family to take her in, Pendeghast petitioned the courts and was made her legal guardian.
Under Penderghast's supervision, Gayle was taught how to use and develop her great powers. Penderghast had plans for Gayle to help him fight a grave menace he believed held the world in its sway. He saw something called "decay" affecting everything and everybody - stripping the world of order and anything that was good. In Gayle he saw a warrior capable of fighting these forces of decay.
By the time Gayle entered college at Chicago's Lake Shore University, her powers had reached their peak and Penderghast decided that it was time for the battle with decay to be joined. Yet Gayle was hesitant to take up the fight, fearing the emotional backlash from her victims would be too painful for her to handle, due to her being a "sensitive" - a reciever of emotions from others.
Gayle was unleashed upon Chicago after a frightening encounter on the campus of Lake Shore University, when she sensed the presence and power of Supergirl and mistook her as an ally of the decay.
Working under the name of Psi, Gayle displayed a startlingly high degree of power in her battles with Supergirl, fighting her to a standstill. However, Psi's reluctance to kill was obvious and Supergirl was able to take advantage of that by playing on Psi's fears. Trapped between the the telepathic urgings of Penderghast and the logical arguments of Supergirl, Psi's fragile emotional state collapsed and she fled in fear from her mission.
Disappointed by her showing and believing she had gone over to the side of decay, Penderghast saw it as his duty to kill Gayle. Though confused, Gayle was still able to defend herself. The result being that Penderghast was turned into the living manifestation of his own worst fears, becoming Decay, a creature whose very touch could decay and rot any and all matter.
Psi later joined the Suicide Squad, Hawk (of Hawk and Dove) is captured by contras in Nicaragua. The Suicide Squad is called in to rescue him or eliminate him if necessary.
An anti-Amanda Waller subset of the government would like to beat her group to the punch. One of them is owed a favor by Valentina 'Negative Woman' Vostock. That agent calls in his marker and the Doom Patrol are suddenly on their way to try and rescue Hawk as well.
The Thinker, The Weasel, Mr. 104, and Psi are put together to go in covertly as Waller decides to use this team to be sent to Nicaragua. Psi is able to use her powers to scout the area psionically and detects the Doom Patrol is in Nicaragua as well. And she is able to use her powers to mask the Squad's presence. We learn that she joined the Squad in hopes of them restoring her memories.
The Squad and the Patrol have a common enemy and so team up. Soon while in battle, The Thinker ends up being killed and Rick Flag throws on his helmet. Like Mento, a suddenly boosted brain makes him addled. He veers to evil and out of control. As Psi is overwhelmed by all these super-personalities around her, her mind is overwhelmed. And that psychic pain means she can't concentrate to use her powers. As she flees the scene, she is blasted from behind by a nameless Rocket Red. The Negative Woman goes to Psi to comfort her. Psi suddenly remembers her past. She remembers her name, her parents, her life, the briefness of her existence than she passes away.
During the New 52, Psi appeared as part of the Circus and now is an interdimentional being who doesn't have a mouth but makes a mental connection to communicate, also it's know that when she arrived earth she fought Vibe and Supergirl giving them a good fight at the end she decided to ask for asylum at A.R.G.U.S.
Marital Status: Single
Known Relatives: Unnamed parents (deceased)
Group affiliation: None
Base Of Operations: Chicago, IL.
Height: 5‘3” Weight: 103 lbs
Eyes: Blue Hair: Black
Other: The new incarnation of Psi has no mouth
Powers and Abilities
Psi wields a vast array of psychokinetic and telepathic powers, and is psychically sensitive. She could also emit a pink aura of force to block Supergirl’s blows or reflect her heat vision back at her. When experiencing great distress, she reflexively teleported away while telepathically hitting Supergirl with her own pain.
Psi apparently could telekinetically reinforce her own body, or was otherwise superhumanly durable - Supergirl’s blows didn’t seem to hurt much, and at one point she was punched through an outer wall and didn’t seem to be wounded. Being unused to super-combat, though, she tended to be disoriented.
Psi displayed the ability to telekinetically rearrange matter a few times, such as when she turned Pendergast into “decay” ; she also once melted a window so she could step through, then reformed it intact behind her.