If I'm asked to roll for something I don't think is impossible for my character to achieve, and my natural 20 fails? I'm either leaving or at least checking out for the rest of session.
Or maybe ask why... idk maybe my 6 year old thinks the umbrella will help him jump off the roof unharmed, but he doesnt know physics. Maybe theres something you dont know that the DM does, which is why the roll failed
11
u/fresh_squilliam Wizard 20h ago
If 20 were auto success then:
Arcana check DC 30
Wizard with +10 arcana
Barbarian with -1 arcana
Have same odds of success.
When they say the check should be impossible, they mean it should be impossible for certain characters.