So what is a blood pact?
You may have stumbled upon it whilst watching Fantastic Beasts: The Crimes of Grindelwald. We had small teasers of it throughout the film and only during the third act of the film was the audience told about it and what it is able to do.
Firstly, the film stipulates that Dumbledore and Grindelwald had created a blood pact which meant that could not seriously harm one another, this later would be regretful for Dumbledore as he could not attack Grindelwald thus send Newt Scamander on his travels instead.
The oath between them both meant they couldn’t fight each other, this was because during this time both parties were extremely close. However, it meant that as Dumbeldore couldn’t fight Grindelwald, it also, in turn, meant that Grindelwald couldn’t eliminate the one person who stood in his way, Albus Dumbeldore.
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