Originally known as Gunbunny, the character first appears in Detective Comics #674 (1994) as the partner of an assassin called Gunhawk. The two are depicted as both business partners and lovers, their tender feelings for one another surreally juxtaposed with their murderous nature and love of assault weapons. After being defeated by Batman, Gunhawk and Gunbunny later return to face his temporary replacement, Azrael, during his stint as the Dark Knight.
Eventually, the two have a falling out and Bunny decides to strike out on her own without Gunhawk. Changing her codename to Pistolera, she abandons the matching green uniform she wore as Gunhawk's partner and adopts a Western-themed cowgirl outfit. She is recruited to The Ravens, an all-female mercenary group led by international assassin Cheshire. As a member of this team, Pistolera becomes a recurring enemy of the Birds of Prey.
After becoming a member of The Society, a vast organization of supervillains, Pistolera is sent to assassinate Knockout, a member of the Society's rival group, the Secret Six. She uses a Thangarian sniper rifle to implant a bomb in Knockout's skin. She survives the explosion. This brings down the wrath of Knockout's lover Scandal, who binds, gags, and tortures her. In Secret Six #2 Deadshot, believing that Scandal could not bring herself to kill a bound prisoner, shoots Pistolera himself.