In the film adaptations of *Harry Potter and the Chamber of Secrets* (HP2) and *Harry Potter and the Half-Blood Prince* (HP6), there seems to be a drastic size difference in the portrayal of Aragog, Hagrid's pet Acromantula, so much so that **one could easily mistake the one in HP6 for one of Aragog's much smaller sons and daughters** which we saw swarming Harry, Ron and Fang in HP2.

[![](https://i.stack.imgur.com/XeHZW.png)](https://i.stack.imgur.com/XeHZW.png)  

**Aragog, *Harry Potter and the Chamber of Secrets* (2002), Warner Bros.**

[![](https://i.stack.imgur.com/3OUPs.jpg)](https://i.stack.imgur.com/3OUPs.jpg)  

**Aragog's Funeral, *Harry Potter and the Half-Blood Prince* (2009), Warner Bros.**

Looking at Fang (the dog) for reference, we can clearly see the dramatic size difference. Not only does Aragog look relatively smaller when using Fang as reference, but Fang is further away, behind a hill (so he'd look even larger when up close to the beast).

Why is Aragog suddenly smaller?

**Side-note:** the designs also appear to be inspired by different species of spiders in the two portrayals. HP2's effort seems to be inspired by a mix of an ogre spider and a tarantula, HP6 is a bit less clear, but obviously different.