>>96120349
Yeah, Zone of Truth is one of those spells that people think is an "I Win" button, but very much isn't. Hell, in previous editions, you didn't even know whether a creature had failed its saving throw--they had to add that so that it wasn't completely useless.

>>96120357
>and the pcs do not know if it worked or not
Your 3.5 is showing. But, yes, it's a spell that you have to think about how you're using.