Shield Charm

• Incantation: Protego
• Pronunciation: pro-TAY-go
• Wand Movement: Not described in the novels.
• Light: The basic charm is typically invisible, often described as a momentary shimmer in the air. It may become visible as a fleeting, silvery barrier upon deflecting a spell. More powerful variations can produce visible light, such as large, glowing domes.
• Effect: Conjures a temporary, magical barrier that deflects or weakens minor to moderate jinxes, hexes, and curses aimed at the caster. The strength of the shield is directly proportional to the skill of the wizard or witch who casts it.
• Type: Charm

The Shield Charm is a fundamental piece of defensive magic, used frequently throughout the Second Wizarding War. In Harry Potter's fourth year, Hermione Granger taught him the charm in preparation for the Third Task of the Triwizard Tournament. Harry used it successfully in the Little Hangleton graveyard to block minor curses from Lord Voldemort, though it was powerless against the Killing Curse. During his fifth year, the Shield Charm became a core part of the curriculum for Dumbledore's Army, as Harry taught it to fellow students to counter the theory-only doctrine of Dolores Umbridge. It was a required spell for the Defence Against the Dark Arts O.W.L. examination. In a notable use, Harry instinctively cast a powerful Shield Charm against Severus Snape during an Occlumency lesson, strong enough to throw Snape off his feet and inadvertently reveal some of Snape's own memories. The charm was used extensively by members of Dumbledore's Army during the Battle of the Department of Mysteries. By the time of the Second Wizarding War's escalation, the charm's practical applications were well-known. Fred Weasley and George Weasley developed a line of “Shield Hats,” “Shield Cloaks,” and “Shield Gloves” enchanted with Protego, which they sold via Weasleys' Wizard Wheezes to Ministry of Magic workers seeking protection. During the hunt for the Horcruxes, Harry, Ron Weasley, and Hermione Granger used the Shield Charm and its variations constantly for protection. Advanced and specialized versions were used to protect large areas during the Battle of Hogwarts:

• Protego Totalum: Used by Hermione to protect their campsites.
• Protego Horribilis: Cast by Professor Filius Flitwick to defend Hogwarts Castle from major dark curses.
• Protego Maxima: Cast alongside other protective enchantments by professors to create a massive shield over the school grounds before the final battle.

The Shield Charm is considered standard fifth-year level magic, but a truly powerful and reliable charm requires significant skill and concentration. It can be cast non-verbally by accomplished wizards, which is a considerable advantage in a duel. There is no specific counter-spell for Protego. It is overcome in several ways:

• Overpowering: A sufficiently powerful curse or a barrage of spells can shatter the shield.
• Unblockable Curses: The three Unforgivable Curses cannot be blocked by a Shield Charm.
• Physical Force: While it can deflect smaller physical objects, it is unclear if it can stop a determined physical assault from a large creature or a non-magical weapon.

The effectiveness of the charm is highly dependent on the caster. For example, when Voldemort's Killing Curse met Harry's Expelliarmus, the rebounding power was so great that it shattered the Shield Charms of all the Death Eaters in the vicinity.

The incantation, Protego, is a Latin word meaning “I protect,” “I cover,” or “I shield.” This is a direct and literal description of the spell's function.

• In the film adaptations, the Shield Charm is almost always depicted as a visible, shimmering barrier of blue or white light that ripples upon impact. This was a cinematic choice to visually represent the magical effect for the audience. (film)
• The Shield Charm is a primary defensive mechanic in nearly all Harry Potter video games, often requiring the player to time its use to deflect enemy spells. (video game)