Lots of New Costumes and Accessories at Party City

In addition to the MLP Puzzle Eraseez, there has also been a huge amount of new pony costumes and accessories over at Party City, just in time for Halloween! Most of the new items are based on Rainbow Dash, but there are also a few Pinkie Pie accessories, Twilight Sparkle costumes and general mane 6 stuff.
Because of the huge amount of items we won't link directly to each item, but you can find them by searching on the Party City website.
(Images from Party City, thanks to tomo for the info)

Costumes

Party City has been selling a few complete MLP costumes for a while, but the ones listed below are all new! Most of them are Rainbow Dash costumes that consist of the loose costume parts mentioned later in this post, but at a cheaper price ($40-$85 per costume).

Loose Costume Parts

You can also mix-and-match the parts of the costumes to create your own partly costume or unique combination. You'll have to pay a bit more that buying a complete costume at once, but you'll have more freedom on choosing what (not) to buy. Most of the items are around $19.99, but prices range from $8 for the glovelettes (arm warmers) to $25 for the adult-sized hoodie. (The Twilight Sparkle costume is currently only available as full costume)

Accessories

There are also some loose accessories for sale of Pinkie Pie, a charms bracelet and various body jewelery of cutie marks and logos. Prices range from $0.99 for the loose cutie marks to $12.99 for the Pinkie Pie headband (which also includes a clip-on tail).