If the first rule of Wicca is Harm None, why are there spells to cause harm?

These are part of black magic. Some people chose to use the powers and abilities to hurt other people. Wiccans are not to use any power to harm other people. There are numerous online sources for dark spell, revenge spells and similar ways to hurt others. I have people approach me looking for ways to hurt people who have hurt them. True Wiccans avoid these practices and the temptation to hurt other people or beings of any kind.

It s like I tell my brother about mental abilities Use the Power for Good. It is also like the force in the Star War saga. Most abilities can be used for good or bad. Wiccans who remain in good standing and follow the Wiccan rules will use their abilities to help people and not to hurt them.