The Snaggletooth rat being near to that of Angun attacked him first. The low-level genesis stage beast didn't have enough brains as they attacked any person that stepped on their boundary. These beasts didn't care about anything and attacked whether the person facing them has a lower or greater cultivation than them and only became afraid when they see a greater group of enemies.
Angun withdrew the broad axe from his back and swiftly striked at the neck area of the Snaggletooth rat. The broad axe sharpness was really great as it was mentioned in the weaponsmith department and easily sliced through the neck, separating it from its body.