What is Maran
Maran (never recommended) is to kill someone with the help of black magic or evil spells. This is strictly prohibited in tantra and can be used in some very specific and defined conditions only. In maran use of tantra, the target is unaware about what is being done to him and the Might works as a deadly weapon.
When to use
Maran is strictly prohibited and can be used as an ultimate weapon for self defence only. When there is no way to save yourself and all powers or methods got failed, then at last, the Maran is used for self defence. This is an offensive mode to protect yourself with the help of the Might which is equivalent or more powerful than that of the used in the sent spell on the target.
How to use
This is kept a secret always in the interest of humanity and used in the supervision of a noble guru. Its use is never told to general public so that it should not be used against humanity.
How to protect from Maran
God is always supreme. Nobody can harm you any way if you are in the shelter of God. Stay in the holy feet of God, Goddess or other divine supernatural power. Be with dharma and become mentally strong. Have faith in God. HE will always protect you from all kinds of evil.
According to tantra, Maran can be stopped using the Maran only from the other side where the Might plays the most important role in it. She kills the negative power being sent and you are protected. It is the Might (the power) only which works in both good and bad forms. It depends on you only, how you use it. Never go against dharma.