Possibly the most important piece of any Harry Potter costume is the Hogwarts-issued Gryffindor House school robe. This officially licensed robe is child-sized to reach ankle length.

If you're going to be Harry Potter, you'll need his round rimmed glasses. This officially licensed costume pair should do the trick!

This easy child-size neck tie is in the same pattern as Harry Potter's Gryffindor house. The maroon tie has golden yellow stripes.

This magic wand costume accessory isn't just for looks! This wand has light effects and three different movie magic sounds.

Play lazy Deadpool with this fun one-piece pajama set for adults. The red, black, and grey PJs include a hood for maxium comfort.

This adult-sized pajama one-piece comes complete with a masked hood and attached cape.

You don't have to wear skin-tight leggings and a bustier to go all Wonder Woman -- just pick up this awesome and comfortable superhero onesie!

Dress up as the hero Superman with this comfy one-piece costume pajamas. This one comes with a cape attached with velcro.

Dress up as the DC Comics character Harley Quinn with this fun adult-sized romper. The red and black one-piece includes a hood with attached mask.

This fun red romper is an adult-sized pajama set in the style of superhero The Flash. Get this and you can zoom off to sleep in a "flash"!

Dress up your four-legged pal as Thor with this adorable two-piece costume, with the vibrant color and style of the old school comic book Thor.

This is a cute bodysuit-style dog costume in Captain America's retro comic book colors of red, white, and blue. You'll get a matching headpiece with the Cap dog shirt.

This great pet costume has your best four-legged friend dressed up as the superhero Spider-Man! With this purchase you'll receive a pet-sized shirt costume and separate mask-style headpiece.

This is an easy, fun tunic-style costume with a detached hood. This costume, like the others listed here, comes in various sizes to fit a variety of dog breeds.

Bring along your very own green monster Incredible Hulk for Halloween this year! This is a fun muscle-look pet costume with a Hulk hood. This would be a great team costume if you dress up as mild-mannered Bruce Banner!

This is one of the essential pieces to the costume. The costume mustache includes non-toxic adhesive to secure it in place on your upper lip.

Wear this monocle between your cheekbone and your brow, or let it hang from your neck with the attached black strap.

Top off your look with this Monopoly Man style hat made of felt. This is a great costume piece that can be used for so many different looks -- a Halloween staple!

Wear this with your white shirt and black coat. It's just like the one the Monopoly Man wears!

Pick up a pack of Monopoly-style play money for your costume. Attach pieces to your hat or coat, have it flowing from your pockets, hand it out while trick-or-treating, or make it rain!

You'll also need a black top coat for the costume. If you don't already have one in your wardrobe, there are a lot to choose from on Amazon, like this one by Lucky Brand.

The Monopoly Man wears grey slacks like these under his top coat. If you don't already have a pair, pick up pants like these from Haggar.

Make it a couple's costume when you pair the Monopoly Man with this pre-made costume tunic. The one-piece costume is worn over the head like a big head scarf and is a funny match with a Monopoly Man costume.