Aragog lived in the Forbidden Forest after he escaped from Hogwarts School where Rubeus Hagrid raised him from an egg. Later, Hagrid brought him a wife, Mosag, and they had thousands of children. Aragog died in 1997 but there was no telling what Mosag did after that.

When Harry and Ron went into the forest to find Aragog, they were horrified to be snatched by huge spiders and taken to see the giant Aragog, an acromantula as big as a small elephant. They were lucky to escape with their lives thanks to the help of an enchanted Ford Anglia formerly owned by the Weasleys.

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