* The original Hetalia: Axis Powers DVDs released in Japan did not include any extra episodes like the Halloween one. Those episodes were released separately on special DVDs or bundled with other merchandise.
* Later releases, like the "Hetalia: Axis Powers - The Complete Series" DVD set, might include some bonus features, such as:
* Extra episodes: This is the most common bonus feature.
* Special interviews: With the voice actors, creators, etc.
* Behind the scenes footage: Of the anime's production.
* Music videos: For the anime's opening and ending themes.
To be sure about the specific bonus content on a particular DVD, you'll need to check the product description on Amazon or other retailers.
Here are some good resources to find information about the Hetalia DVDs:
* Amazon: Search for the specific Hetalia DVD you're interested in and check the product description.
* Hetalia Wiki: This wiki has information on the anime and its releases, including DVDs.
* Hetalia fandom websites: There are many fan-run websites dedicated to Hetalia, which might have details on bonus content.
Hopefully, this helps!