Odds of a Critical Success with Advantage, or a Critical Failure with Disadvantage, using the following homebrew rule:
- Critical Success occurs when a roll has advantage, one of the dice is a natural 20, and the other die is high enough (with modifiers) to pass the check
- Critical Failure occurs when a roll has disadvantage, one of the dice is a natural 1, and the other die is low enough (after modifiers) to fail the check
DC is what the die needs to roll to succeed on the check, before modifiers.
- Critical Success occurs when a roll has advantage, one of the dice is a natural 20, and the other die is high enough (with modifiers) to pass the check
- Critical Failure occurs when a roll has disadvantage, one of the dice is a natural 1, and the other die is low enough (after modifiers) to fail the check
DC is what the die needs to roll to succeed on the check, before modifiers.