How much does a sack of dirt weigh? You’d imagine Indiana Jones asked himself that at least once! 😉 Funny though, my players almost never do.
The best traps to spring on players though are ones that have triggers. Anytime a player can unwittingly set a trap in motion, it makes the game that much better. Having the sense of consequence for an action, whether or not a player is cognizant of what they’ve done almost always enhances the game.
It brings people into the story in a different way, and makes them consider how they explore the dungeon in a different way. True, sometimes this turns into people making it a needless exercise in thorough dungeoneering. Not always though. Sometimes it helps people re-assess what they’re doing, and they think again about how they do things. It introduces caution. This helps change strategy, and that’s a positive.
Also, it can encourage a change of tactics. If people become aware of previously unsuspected threats, then they might bring a more strategic approach to the game.
Player 1: “Ok, there’s some weird traps here. What can we do to not get killed?”
Player 2: “Hmmm…, good question. Well, I have X ability. Maybe that would help.”
Player 3: “Right, and I can do Y. That could be good as well.”
This is just what the result of a trap could cause, but as a GM, this is where I want to be. I want to see people discussing the game. Working together. This is goal for me. The more I can bring people together at the table, the more I’ve succeeded. Traps can make that happen. Traps people spring on themselves are a good example.