Random Things About The Rules Of Magic In The Wizarding World (15 items)

(#4) Ghosts Only Get One Chance To Move On

Nearly Headless Nick expresses some regret to Harry for his status as a ghost in The Order of the Phoenix. He doesn't know if he will get another chance to go into the afterlife; the truth is that it isn't possible. A witch or wizard is given a choice at the moment of their death to move on, which is a one-time offer.

A person doesn't get the chance to turn back should they decide to become a ghost, meaning they're trapped as an echo for all eternity. The permanent state of a spirit is proven through the Bloody Baron and the Grey Lady, who are ghosts from a thousand years ago.
(#15) It's Impossible To Resurrect People Through Magic

In Deathly Hallows, Harry uses the Resurrection Stone to bring his loved ones to him. The magic of the stone can't bring someone back to life, however, so they aren't truly back. They are echoes or souls of people Harry wants to see, and that's the extent of a person's return to the land of the living.

As it is, no magic can keep death at bay - Voldemort simply delayed the inevitable with the Horcruxes. Studies are ongoing at the Ministry of Magic through the Veil Harry and his friends came across. Nothing conclusive has ever been uncovered and wizards currently have no choice but to either accept their deaths or return as ghosts.
(#10) No Level Of Magic Can Domesticate A Dragon

Dragons can't be kept as pets, no matter what Hagrid claims. Hagrid was lucky he had Harry and his friends to get Norbert to Romania in The Sorcerer's Stone before something disastrous could happen. Dragons are meant to live in places with mountains, and there are centers to house the ones that need to be kept safe.

Keeping a dragon as a pet is illegal and the Ministry of Magic can convict a person for their possession of this creature. Charlie Weasley works in a dragon research center, so he is a licensed expert who works around dragons. However, Charlie doesn't work on domesticating these creatures; his work is to ensure they are safely bred without harming themselves or humans.
(#13) Wizards Are Perfectly Capable Of Doing Magic Without Wands

In The Prisoner of Azakban, Albus Dumbledore points toward Harry as he falls from the sky to immobilize him in midair, which attests to his innate magical ability. While witches and wizards usually use wands in the main Harry Potter series, they don't actually need them and can be trained to do the same magic on their own.

Students at Uagadou, a wizarding school in Africa, are trained to become experts in Transfiguration, Alchemy, and Astronomy. All of their magic is accomplished without the use of wands, as the entire continent of Africa completes their magical needs using natural magic.
(#7) Dark Wizards Who Attempt The Patronus Charm Will Be Killed By Their Own Wands

Raczidian was a dark wizard who lived in a castle surrounded by dementors and grew to have control over them. His dementors were driven out by a hero known as Illyius through the use of a Patronus charm. Raczidian had never witnessed a Patronus before and considered it a spell of immense power that he wanted to use.

Unfortunately for Raczidian, he learned the hard way that a dark wizard is incapable of casting a Patronus. Raczidian's attempt resulted in his wand sprouting out so many maggots that they covered him entirely until the maggots devoured Raczidian whole.

Raczidian is an example for all dark wizards about the extent of magic they can use, with Voldemort and his Death Eaters also shown to be incapable of casting a Patronus.
(#1) A Muggle Can Perish If They Try To Do Magic With A Wand

Albus Dumbledore was very polite when he refused Petunia's request to enroll at Hogwarts as a child. As it turns out, Dumbledore was also protecting Petunia's life, as Muggles can't handle wands. Not only do they lack the inherent magical ability, but Muggles are also in danger if they take hold of wands.

Should a Muggle get their hands on a wand and try their hand at magic, something violent will happen at the cost of their lives. Wands are meant to be carried by wizards, and even then they are loyal to the ones they choose. Muggles are in danger if they handle wands, as the magical devices are not meant for them.