Mnemonic Kid was a rejected Legionnaire applicant, who could induce memory loss.
Angry that she had been rejected, she plotted her revenge by wiping parts of the Legionnaire's memories. Another Legion reject, Fortress Lad, came to the rescue by transforming into a giant fortress in order to protect the Legionnaires.
Mnemonic Kid continued to use her powers against Fortress Lad, who resisted at the cost of losing all of his memories. As a last resort, Mnemonic Kid threw a grenade at Fortress Lad (and the Legionnaires inside him), but she caught the impact of the explosion herself and died.
Powers and Abilities
Mnemonic Kid had the power to induce memory loss, but could not return it once it was taken away.