Detective Comics #628

HEARTS

At the Penguin's former hideout, an ornithologist has been tasked with indexing the thousands of birds in the place. He is interrupted by Abattoir, who murders the man by removing his heart and kills all the birds.  The gruesome crime gets the attention of both the GCPD and Batman, who goes to Arkham Asylum to interrogate the Penguin and learn any information that might help him solve the case. Much to Batman's surprise, Abattoir is locked in his cell and the administrator of the asylum has no record of any recent escapes.  That night, Abattoir is released from his cell by members of the cleaning staff and they take him to a dairy plant, where he intends to kill all the cows and use their hearts. The police get an emergency call from the plant and Batman learns about the situation. He leaves the Batcave in the Bat-Copter and tells Alfred to find any connection between birds, cows and probably rituals.  Batman confronts Abattoir at the dairy plant, but the madman destroys the Batcopter and escapes. Upon returning to the Batcave, Batman learns that Abattoir is indeed performing an ancient ritual to gain immortality. The ritual consist of killing 200 birds, 400 co