Buffy the Vampire Slayer: Season Nine #15 (2012)

Billy the Vampire Slayer, Part Two
Training has begun, bringing the newest Slayer and Watcher closer together. Will they be ready when they're needed most? The rapidly growing zompire population has overcome a local institution, and our heroes in training must take on the fight of their lives! Buffy show writers Jane Espenson (Once Upon a Time) and Drew Z. Greenberg (Warehouse 13) reunite in this special two-part story about a young duo coming together to fight the forces of evil and discover their role in this strange, new 'verse.
Release Date: 2012