The One D&D Character Origins playtest has the following rule for d20 tests:
If you roll a 1 on the d20, the d20 Test automatically fails, regardless of any modifiers to the roll.
Using 5th Edition classes from the PHB as the One D&D Playtest states you should, if a character has at least 11 Rogue levels, they get the "Reliable Talent" class feature:
By 11th level, you have refined your chosen skills until they approach perfection. Whenever you make an ability check that lets you add your proficiency bonus, you can treat a d20 roll of 9 or lower as a 10.
What happens if you then roll a natural 1 on a roll with which you would normally add your proficiency bonus? Is the natural 1 neutralized or is it an automatic failure?
Is the same true of similar features such as the barbarian's Indomitable Might?
Why ask this question?
Often in games I play as a rogue character, and I have wondered about how this will interact with the 1D&D rules. In the past we have always said that 5e doesn't have crit failures, so you don't have to worry. Now that we do have crit failures, this situation needs to be resolved. Features like this are fairly common so I'm pretty sure this situation will come up. I'm not too sure what the answer is here which is why I made the question, I would like to understand when crits apply on checks. Obviously with attacks when you roll the die it applies and we modify that afterwards but it remains a crit no matter what, I'm guessing the same will be true of other tests.
Best Answer
You didn't roll a 1, you rolled at least a 10.
The feature lets you treat anything less than 10 as a 10, so you roll a 1, but treat it like a 10, not like a 1.
Most similar features have wording to that effect, you basically replace the dice roll and pretend it landed on whatever the new number is.
The new language might be “wrong” but that's why it is playtest material. Try your games using this interpretation (the right one) and try letting people fail on a natural one despite features that let them succeed and pass your feedback on.