No. Normally, when you use a credit card, you ALSO need to know the little security number that's on the BACK of the card. It's illegal to use a card that isn't YOURS, by the way. That's identify theft and that's a felony -- 10-20 in the big house. Even if you're a minor, you'll be in some deep doo-doo. Don't do it. Runescape's not worth becoming a convicted felon.