Batman Legends Of The Dark Knight #37 1992

Batman Legends Of The Dark Knight #37, titled "Mercy," features Gotham police officer Mercedes Stone seeking vengeance after her partner is brutally murdered by the street fighter known as the Cossack. Batman trains her, but she ultimately enters the illegal "Blood Pit" fighting circuit to confront her foe. Batman intervenes, but Mercy is fatally wounded during the intense battle, highlighting the grim consequences of revenge. This standalone story is notable for its exploration of Batman's moral code and the darker, self-contained narratives characteristic of the Legends of the Dark Knight series.