And he'll lose the battle of Armageddon before it starts. The big lie here is faith alone saves. People are flocking to churches who don't follow the Ten Commandments and accept any sinful lifestyle imaginable. Judgement Day will be how you live your life according to your religion, not what you believe.
The Good works come in the sanctification process. God does the work through us. First we must be born again and justified however. The first step is to be poor in spirit and have a need for our Savior.