A: Most Surprises specify a type of card or game action which it reacts to. This specification isn’t a permission so much as it is a restriction. Not having one doesn’t mean it has no permissions, it means it has no restrictions.

In other words, if there is no specific trigger listed, it means that the Surprise can react to ANY kind of play. Think about it: if a triggers were permissions, and a Surprise could ONLY respond to a trigger listed, then NOT listing one would mean that it couldn’t be played in response to anything, and it wouldn’t be playable out-of-turn at all, which defeats the purpose of a Surprise.

Since there are so many possible game actions or card types one might want to use My Turn Next in response to, it doesn’t make sense to have to list all the times it CAN be used. Rather, it makes sense to simply not list a restriction at all. You can play it “in response to” ANY game action by another player.

Some examples:
You might play it in reaction to a Hand Limit, so that you don’t have to discard it. You might play it in reaction to someone Trading Hands with you, so you get to use it instead of giving it away to them. You might play it because someone has played a Goal you need so that you can play your winning Keepers ASAP before someone changes the Goal to something else.