according to the back of the Party Set box, it says it includes:
5 invitations
5 party hats
5 horns
4 hair ribbons
6 plates
6 cups
Cake w/Candles (6 slices)
Cake platter
2 blindfolds
Pin the Tail game (w/2 different pony tails)
Banner (It's Party Time" folded card w/3 party hats)
Balloon
Greeting Card (It's Party Time" w/Best Wishes)
Present
Party Panties w/box
Blanket ("It's a Party")
Brush
Hairpick
Scented Body Sticker (Best Wishes as a pony, not pegasus. Some packs came with other pony stickers like Hippity Hop)
Information received from picture of the packaging from auction w/the set on ebay. The information in the parenthesis is additional descriptions of the items as know them to be.