Well, I was sorting my Pokemon cards by rarity. I'm sort of a noob when it comes to Pokemon cards. I sorted them into piles like ones that have a black circle in the corner, ones that have a black diamond in the corner, black star, silver star. I saw some, a Diancie EX, a Mega Diancie EX, and a Mewtwo EX that had no symbol, but they all had a bigger black star with "PROMO" written across it. I put them all in a pile. But, one of my last cards, a holo male Meowstic, also had that black PROMO star. It was not an EX, not a Break, and I couldn't find anything different about it. Why did it have the "PROMO" symbol?