Idiotic Mind (5e Feat)
From D&D Wiki
Prerequisites: A negative Intellect modifier
Due to your lack of intellect, to other people, you seem too stupid to tell a lie.
- Increase your Charisma score by 1, to a maximum of 20.
- For the sake of Deception checks, you may add your negative Intellect modifier with your Charisma modifier, counting negative Intellect as positive for these checks.