Name and aliases: April Dumaka of Earth
First appearance: Legion of Super-Heroes v.3 #33 (Sept. 1992)
Legion 1.5 (v.4)
Little is known about April Dumaka's past. During the Dominator occupation of Earth, she was kidnapped and experimented on in their underground chambers, where her metagene was activated, turning her into a cat-like girl, with claws, heightened senses, superhuman agility, and making her quite sexually aggressive toward men.
Fortunately her chamber was near Danielle Foccart's. Danielle could "talk" to computers and sensed their impending destruction. She freed them along with Xao Jin and Bobb Kohan, and the four of them escaped death in the chambers. (Legion v.4 #33)
While seeking shelter, they encountered the SW6 Legionnaires, Lightning Lad and Saturn Girl, who took them to their command post. There April got accustomed to her new self and when Reep Daggle decided to help establish the SW6 team on New Earth, he brought April into the group. He gave her the super-hero code name of Catspaw. (#41) There she was content to chase the boy Legionnaires like mice.
This era of post-Crisis Legion continuity ended with the coming of Zero Hour. Catspaw vanished just before the end. (Valor #22) The v.4 Legion's timeline is no longer valid, on any parallel Earth.
Legion 2: Earth-247
The Catspaw of Earth-247 made only a cameo appearance. She was seen as a candidate under review by Leland McCauley as a prospective member of his Workforce. (Legionnaires #69)
This universe was destroyed during Infinite Crisis, and Catspaw along with it (though the Legionnaires survived).
Tom Bierbaum said that Catspaw was created by artist Jason Pearson, and added:
"At one point he and we were trying to work out a "Legionnaires" fill-in that would have given more of her background, but we didn't start thinking about that possibility until our time there was almost up. Basically, Catspaw was just a woman on Earth when the Dominators were secretly nabbing people and experimenting on them. There was a boyfriend character (from the Legionnaires story where they meet all the Protys on Antares, I think his name was Ansis) who was supposed to have somehow betrayed her and been the cause of her being kidnapped by Earthgov/Dominators."