The Arrancar Make Hollow Power Look Organized
Episodes 110–116 · Arrival Arc
The first Arrancar attacks change the meaning of Hollows. These are not isolated predators wandering into Karakura Town; they are armed, ranked and reporting to Aizen. Soul Society responds by stationing Shinigami in the living world, while Ichigo discovers that the Hollow inside him is becoming as dangerous to his confidence as the enemies outside.