The Street Angel
Alongside Mister Badd, he broke into Dr. Lewis Oscar Croft's lab and freed the woman who would become Black Velvet. After sometime she relocated to Astro City and the Street Angel started hanging around her more. This is the point in late 1976 that Street Angel went "dark"(matching the tone of the age), becoming a violent vigilante. Following this dark phase, in contrition, Street Angel orchestrated mercy missions, bringing medicines to Central Africa for several years.
He returned to Astro City in 1984, teaching young kids boxing and self-defense. He also took Quarrel II under his wing, who seemed to revere him. The Blue Knights revealed some unpleasant past events that left Angel feeling depressed and suicidal. A chance encounter with the Silver Agent provided a lifeline back. He maintained his role as a vigilante , atoning for his past. Disaster struck when he was attacked by the Pale Horseman rampaging throughout Astro City. Angel's last actions saved the lives of Otter,Mister Toad and Owl, but at a dear cost. The Pale Horseman incinerated him like so many others being "cleansed" by his merciless interpretations of justice.
A highly trained martial artist and extremely agile acrobat, the Street Angel carries a supply of large Aerobie-like rings ("halos") which he hurls at enemies. In his earlier, more light-hearted days, he used a variety of specialized halos; each type performing a different technological trick. When the Street Angel entered his darker phase, he switched to halos with steel cores and angel-shaped shurikens to disable and physically damage criminals.
He had several different looks in appearance. In the late 60's he had an single mask with a lighter blue and white costume, before adapting the hooded look in the early 1970s.
He was known to have some relationship (not necessarily romantic) with Quarrel II. This probably occurred after his mercy missions in Africa. He may have been her teacher or mentor, guiding her to become a hero, not a criminal mask like her father: Quarrel.
The super-villain Ominuss was supposedly murdered by Street Angel in 1988. How this jibes with his fatal confrontation with the Pale Horsemen four years earlier is unknown. It's could be a mistake by Supersonic meaning 1968 or 1978, or even the wrong hero.
An old newspaper article, circa 1995 or slightly before, states that Street Angel is "presumed dead." Mr. Bridwell would have likely had a decade old clipping.