I am not finding alot about the rolls of Natural 20's. I am being told by the old DM who is now a player that naturals are automatic successes on everything. For example. On a perception check there is nothing he does not see, hear or smell even if it does not seem logical that he knows all. Or a Paladin sees him commit a murder and rolls a 20 on a diplomacy check to see if he can talk him into letting him go and thus should be given a free pass. This does not make sense to me so I was wondering if someone can give me clarification. The only thing I see is that it is an automatic hit in a fight. Which doesn't make much sense because if you need more than a roll of 20 to hit something you should not be fighting it.