While playing, we found ourselves in front of an NPG who was telling us something and a character wanted to try to understand if he was lying or not! Unlike D&D, there is no ability, like intuition, to use! We thought of a test opposed between the NPG's Cheat and the PC's intelligence test!
It made sense until we saw that there is a heroic ability, PERSPECTIVE, that allows - precisely - to do it!
So the question is: the idea of the opposed roll will be good but not "valid"!?