DensArmor Plus. You can get it at home depot also. It's almost twice the price of regular though. Instead of being paper glued on each side of the gypsum, it is a silicone core with gypsum on each side, and faced with fiberglass that is heat embedded on each side of the board. It's supposed to resist mold really well because mold grows better on the paper. So no gluten and corn either like regular drywall.