If you're thinking about having a wand made with Acromantula web, you're probably a fan of having your wand confiscated by the authorities. Using a wand with this core has been illegal in Britain since 1782, after it was discovered that the wielder of an Acromantula web wand has particular ability with Dark magics, especially the Imperius curse. There are certain diplomatic exceptions, as it is a traditional core for Asian wands, but even those are temporary, and many wizard diplomats on long-term assignments find themselves compelled to procure replacement wands for their stay.