Snake Tongue

Successfully persuade, bribe, and intimidate (all three) in dialogue. These are the [Persuade]/[Bribe]/[Intimidate] speech options that pop up in conversations - do each successfully at least once across your playthrough. Persuade wants decent Speech (or the right perk), Bribe needs gold, Intimidate is easier with a strong character. You'll get all three naturally as speech checks come up.