Batgirl and the Birds of Prey (Rebirth) TP Vol 01 Who Is Oracle

In these tales from BATGIRL AND THE BIRDS OF PREY #1-6 and REBIRTH #1, a mysterious new criminal operative called Oracle has declared war on Gotham City! Barbara Gordon, a.k.a. Batgirl-and a.k.a. super-cyber hero Oracle-in a previous guise, takes exception to someone smearing her legacy. Can she count on Black Canary and the volatile Huntress to help her get to the bottom of this mystery?