| Great quiz, Flick! And yes, you are right that Prior Incantato is a spell while Priori Incantatem is something that may happen in a duel. Here is what the HP Lexicon says (Don't be confused where it says "also;" I am quoting the lexicon entry for prior incantato which also covers priori incantatem):
Prior Incantato (prye-OR in-can-TAH-toe)
also: Priori Incantatem
"Reverse Spell Effect"
"prior" L. former, earlier, preceeding + "incantatare" L. to bewitch or enchant
Can be cast as a spell, ("Prior Incantato"), in which case it forces the target wand to emit a ghost image of the last spell it cast. The images can be dispelled using Deletrius.
When two wands are forced to duel that have core material from the same single creature, the result will be "Priori Incantatem," a display in sequence of the last spells one of the wands cast. Which wand will show the spell effect depends on the willpower of the two wizards involved.
Amos Diggory cast this on Harry's wand to discover whether it had cast the Dark Mark (GF9).
When Harry and Voldemort duelled, their wands, which share a core of a feather from the same phoenix, were linked in the Priori Incantatem effect (GF36). |
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