I'm a new DM, and I'm running through the Starter Kit adventure ( "Lost Mine of Phandelver "). At one point there was an opposing skill check for one of the PC's trying to sneak -- Stealth vs Perception. The player rolled a 20, and there was a bit of discussion about whether that was an automatic success -- similar to Critical Hits.
So, I'm wondering:
- Do all opposing skill checks automatically succeed on a natural 20 ( unless there's a tie )?
- If not all opposing skill checks automatically succeed on a natural 20, do any of them? If so, which ones?
- Besides saves & attack rolls, what treats a natural 20 as an automatic success?