Reverse Spell
From Absit Omen Lexicon
Spell Name: Reverse Spell
Incantation: Prior Incanto
Pronunciation: PRI-or in-can-TAH-toh
Spell Branch: Charms
Magical Discipline(s): Defensive
Appearance: Emits a gold light.
Description: The charm is directed at an intended wand, forcing the wand to regurgitate previous spells. If both wands involved share a core from the same source (such as with Harry Potter + Lord Voldermort), the reverse spell manifests as "priori incantem".
Regulations: Controlled
Skill Level: Intermediate
Etymology:
References:
Notes:
More information can be found in the Harry Potter Wikia: link