Q: How do Surprises work? I added some to my game, but they’re not in my rulesheet.

This card can be played when it’s not your turn, to cancel a card being played. During your turn, it works like an Action.
A: Here is what it says in our rulesheets about Surprises:

These cards can be played at any time, even when it isn’t your turn. Surprises have two functions, one for during your turn, and one for out-of-turn.

A Surprise can also be used to cancel another Surprise.