This curious item almost isn't a party supply. It's more like a promotional item. It was made by Sega and given out to invite people to their vendor booth to meet a mascot suit Sonic. It's made to look like a regular invitation card you might get in the mail for a party...however it's likely it was only given to the press or official people who were already invited to the convention/game show/E3 or whatever this party was already a part of. (since it takes place in a booth) The details are the where (booth #) and what time of day to go there. Still, this is quite an unusual and interesting item to see.