"...we have achieved correct identification of the potion's ingredients by Scarpin's Revelaspell..."
-- Horace Slughorn (HBP18)
Used to identify the ingredients of the target potion or the enchantments on a target object. May also be used to untransfigure those who seek to hide their true identities.
References from the canon
- Used by Hermione on the Half-Blood Prince's copy of Advanced Potion-Making (HBP9) She also used the spell silently during Slughorn's N.E.W.T. Potions class over a phial of poison so she could brew the antidote (HBP18).
- Used verbally over a cauldron by Ernie Macmillan (HBP18)
- Possibly used silently by Dumbledore when he poked his wand into the purple armchair at Horace Slughorn's house to reveal that wizard's transfiguration (HBP4).
- Attempted by adult Draco Malfoy with the incantation reversed to "Revelio Specialis" in the bedroom of Voldemort's daughter, Delphi, to discover what she was hiding at St. Oswald's Home for Old Witches and Wizards (CC3.21). It failed to reveal anything since only the sound of Harry speaking Parseltongue would unleash Delphi's hidden prophecy from the hissing oil lamp.
- Shortened version of the incantation "Revelio" used by Tina Goldstein and Newt Scamander to untransfigure Percival Graves into his real form as Gellert Grindelwald (WFT). This may be the spell with a "flash of blue light" used silently in the Shrieking Shack by Sirius Black and Remus Lupin to transform Peter Pettigrew from his Animagus rat state to his human form (PA19).
Latin for "reveal the particulars"
May sound similar to Snape's "Reveal your secret" and "Show yourself" that he pronounced over the Marauder's Map (PA14), but that falls under the description in Miranda Goshawk's Book of Spells, Chapter Two, as the Revealing Charm, which renders invisible ink visible using the incantation "Aparecium" (BoS).