Hi Jill!
Welcome back to the Disney Parks Moms Panel.
Mickey's Halloween Party is such a spooktacular fun time and I'm excited for you and your kiddo to experience it all!
The costume guidelines for the party depend on age and Guests under the age of 13 are able to wear somethings that older Guests can not. For Guests under 13, the guidelines state that "Costumes and some masks may be worn, as long the mask does not cover the entire face and eyes are visible." Depending on exactly what kind of mask comes with his costume, he may be able to wear it, but based on the traditional
Darth Vader masks I've seen, he'll likely be asked to remove it. If you would like to bring it with you for potential
PhotoPass opportunities that would probably be okay, but he will not be able to walk around with it if his entire face is covered.
If you would like to put your costumes in a locker beforehand, you'll find
locker rentals in the esplanade outside of Disneyland Park to the left of the main entrance. Please let us know if you have any other questions!
-Lindsey ºOº