Hidden in the hand of any player could be a scary sneaker card. Sneaker cards are cards that must be played without being seen either until a condition is met, or just never. These cards can be played up-side-down, under other cards, or not at all and you still gain their effects. They must come with proof that you did really gain the points and did not just say so.
These cards can be played as traps for other players. For example " The next player that states a question recieves this card. That player loses half of their cards"
Alternatively these cards may be made to secretly get points, for example " if you you can write on a blank card what you ate for breakfast this morning, then slip it into the discard pile without anyone noticing, you gain 50 points, if not you lose 50 points"
Passing Sneaker Cards
These are sneaker cards that pass from person to person. They can end up with some pretty wacky results, by making people do things that they never would normally do and without any apparent reason. for example (again) if you draw a card that says "If you receive or draw this card, you must suddenly change the conversation to something regarding ostriches. Then casually slip it into the deck. Then, the process continues, but they must be played in large groups.