What are easy ways to destroy a Paper Bag? Burning, soaking, extreme voltage, dangerous chemicals, liquid nitrogen, meteors, using an ouija board to have spirits do it for you, and Dracula's moon laser. What's less effective? Throwing rocks at it, biting, earthquakes, and punching your way out of it. (The Mythbusters can tell you how hard that last one is.) What do the easy ways have in common? They're like types that are usually special attacks. (Fire, Water, Electric, Poison, Ice, Dragon, Ghost, and Fairy) What do the less effective things have in common? They're like types that are usually physical attacks. (Rock, Dark, Ground, and Fighting.)
By the way, who's going to abuse this in this gen's Battle Tower? >:D