What were the changes Philip II made in his army?

Philip II established an army of full-time, well-paid, highly skilled soldiers. He developed new weapons for his army: catapult machines - that could throw burning spears or rocks over walls; battering rams - that could smash through strong gates. He improved the Greek phalanx into 16 lines, in which soldiers held 6-meter long spears. He also developed a high-skilled cavalry.