Complex sentence: They made stiff resistance to Arjuna:-Armed with machines vomiting from their throats (mouths?) iron balls and bullets, and catapults for propelling huge stones, and rockets, they approached to strike Krishna and Arjuna, their energy and strength increased by wrath.
Split into simpler sentences: They made stiff resistance to Arjuna:-Armed with machines vomiting from their mouths. Iron balls and bullets, and catapults for propelling huge stones, and rockets, they approached to strike Krishna and Arjuna, their energy and strength increased by wrath.