FrogReaver
The most respectful and polite poster ever
I wasn't accusing you of not wanting to challenge your PCs. I was saying that challenging a character's weak points can be a good thing as long as it's not overdone.
I disagree that it is auto failure. It's a challenge for the character to hold his tongue THIS ONE TIME. Not unlike a caster being confronted by a golem needs to figure out a different way of dealing with the threat than their go-to methods. It's not an auto-failure, but an opportunity to go outside their comfort zone. Admittedly, these sorts of challenges are more likely to result in failure because they target something that the character/party isn't adept at handling. So, yes, be prepared for the possibility of failure (although I feel that goes for less difficult challenges as well, since it's always a possibility).
holding your tongue isn’t an action. It’s doing nothing. A wizard confronted by a magic immune critter will not do nothing. There’s lots of other things for him to try.