Re: Moldy Cardboard
Well it ain't good, but if you clean up the mold and keep the game dry you should be OK. We live in an incredibly damp apartment, and run two dehumidifiers to keep the humidity down. We have a game "shelf" and a game "closet" and each has a dehumidifier near it. I try keep the humidity below 40%, which is probably lower than necessary, but I rest easier knowing all the money spent on games isn't moist and moldy. I've never had mold originate in our apartment, but I have received or bought games that had mold. With good clean-up, several days to dry out, and low humidity I've never had mold return.
If you've had mold issues with two games, I'd check the rest of them too. Clean them ALL up, and if you've got high humidity then find a way to bring it down. Mold can and will spread if it's able, so your best option to get rid of all of it and then do preventive care from that point forward.