#2 because it's gonna be a sword on 70% of the planet. Especially since you live in a magical world with fish people and spells that make you breathe underwater and protect you from pressure,etc, etc. Meanwhile the first sword lets your enemies know you are hungry, which a really smart enemy could take advantage of.
Age is measured from the moment of birth rather than the moment of conception, so fetuses have negative age. I suppose if you killed enough negative-age fetuses, you could live forever.
I mean, it does raise some obvious ethical issues, but...
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