I've only just identified something which has been bugging me for literally years.
Why does the executioner Fudge brings to kill Buckbeak use an axe?
Seriously, one Avada Kedavra and it's done with zero pain, zero mess and zero effort.
Possible arguments and why I think they're wrong.
- Not every wizard knows how to use the killing curse. - Sure, that's true but we know the Ministry of Magic employs aurors, and employs someone purely to execute dangerous animals. So that wouldn't be a problem.
- It's an unforgivable curse, it's illegal. - The fake Professor Moody makes it clear that the unforgivable curses are only illegal when used against a fellow human being, then uses them on spiders by way of demonstration.
Here are some possible real-world, fiction writing, reasons (I'm not looking for these):
- The image of an executioner with an axe is a frightening and dramatic image.
- The sound of the axe coming down gives the kids a reason to falsely think Buckbeak has already been killed.
- This might make it easier for Harry and Hermione to escape with Buckbeak.
So, are there any in-world reasons the ministry would choose to use an axe instead of a spell?