I’ve never heard this before! I love it.
the bat thing came from Vlad the Impaler sending swarms of bats in his enemies at one point, late at night. (I believe also where the sun myth game from)
garlic has always, since like ancient egypt, been used to ward off evil and supernatural beings, and was always thought to have great healing powers. it was also in folklore (and in some actuality) a good repellant against mosquitos and other blood sucking insects, so it might’ve gotten it that way too, among other things