DC Comics great Archie Goodwin laid it out exactly the way I remember it in his introduction to the Batman: Sword of Azrael collection in 1993: "[Joe Quesada]… showed his artwork to DC editor James Owsley, who assigned him to the TSR fantasy book Spelljammer, then The Question Quarterly, and ultimately to the successful miniseries that brought Joe to everyone's attention, The Ray. At the time he agreed to do Sword of Azrael, Joe was already in line to take over Marvel's popular X-Factor book and had become an official 'hot artist'." A Batman-related mini-series published during the landmark Knightfall storyline, the series and its creators certainly made their mark in Batman mythos history. There's a Batman: Sword of Azrael #1 (DC, 1992) CGC NM/MT 9.8 White pages up for auction in the 2021 September 26-27 Sunday & Monday Comic Books Select Auction #122139 from Heritage Auctions.
Goodwin also explained something I'd always wondered about when Azrael debuted in his own mini-series rather than being worked into one of the regular ongoing Batman titles first: "To give this new character the depth and importance required, it was decided to introduce him with a full-blown origin story. With the regular Batman titles already heavily committed to their own parts in the newly unfolding continuity, Legends of the Dark Knight was the most likely spot to present this seemingly separate but ultimately integral part of the Batman mythos. Except I didn't have an open spot for it at the time it would be needed to mesh with the developing events in the other Bat titles."
And so it was that comics superstars Denny O'Neil and Joe Quesada developed Azrael's debut in its own mini-series. An underappreciated moment in the Batman mythos, there's a Batman: Sword of Azrael #1 (DC, 1992) CGC NM/MT 9.8 White pages up for auction in the 2021 September 26-27 Sunday & Monday Comic Books Select Auction #122139 from Heritage Auctions.
Batman: Sword of Azrael #1 (DC, 1992) CGC NM/MT 9.8 White pages. First appearance of Azrael. Joe Quesada and Kevin Nowlan wraparound gatefold cover and art. Overstreet 2021 NM- 9.2 value = $20. CGC census 9/21: 490 in 9.8, none higher.