Not much is known about the Legion of the Doomed, they are demonic creatures that come from a fiery realm. In their first recorded appearance, one of their members appeared before Ella Waltin, leaving her a child for her to care for. While she agreed to do so the child's strange eyes and adult sounding voice unnerved her. This led to a call to Dr. Jack Castle, secretly the costumed hero known as Fiery Mask. Castle would find the child's strange voice suspicious as well.
Soon a series of bizarre and violent murders would happen across the city prompting Fiery Mask to investigate. What he would find would be a demonic creature. Following it as it went through the city, he would track it back to the Waltin home. There, Fiery Mask would be horrified to watch as the small child would suddenly transform into the creature he had been tracking. Attempting to stop it's next nightly murder spree, Fiery Mask would fail to stop it from killing two new victims. Attacking it, the creature would attempt to teleport away, taking Fiery Mask to his realm with him.
Attacked by two winged demons, the hero would easily defeat them. Suddenly a massive demonic creature -- presumably their leader would rise from the flames and banish Fiery Mask from the realm. Fiery Mask would wake up in his office in his civilian guise wondering if the whole experience happened. Checking the morning paper he would see that the string of murders mysteriously stopped, and that their last victim was Ella Waltin's husband Ab.
The purpose of the Legion's murder spree and their use of Ella Walton remains unrevealed.