The Battle Begins (開戦, Kaisen) is the fifteenth chapter of the Fire Force manga series.
Aboard the Special Armoured Fire Engine, the Special Fire Force Company 8 excluding Akitaru Ōbi arrive at the scene. After talking with Takehisa, Shinra makes him move toward Iris' location, avoiding the likes of the 5th grunts using his Ignition Ability. Takehisa then begins his attack on the grunts that stand in his way, using his guns to take them out without killing them. As Tōru spots them unknowingly, he attempts to use his Backdraft Bubblish Gum ability to get rid of Takehisa, but Maki successfully fades out the explosion, leaving no harm. Takehisa assumes the opponents location and uses his Bullet Speed Control to aim his bullets toward him, and finishing him off with his Ricochet Control. Thinking he had it easy, Takehisa remarks that the two newcomers of the 8th would've been a more difficult opponent. As he orders Maki to interrogate the grunts to talk about the data they have on the Flame Humans, the 3 Angels of the 5th appear. Arthur, ordered to follow Shinra by his Devil Footprint's, finds himself far behind Shinra as he's so fast. He stumbles upon a member of the 5th with a seemingly cone-shaped head, to which he jokingly points out. The 5th member tries to scare off Arthur, and Setsuo then appears from behind him, whispering killing intentions to himself. As Arthur remembers his face, he prepares himself for a showdown.