Zircon's Deductions (5e Feat)
From D&D Wiki
Prerequisites: You must be a Zircon Gem.
As a Zircon you have a natural inclination to deduce and infer about your opponents and allies alike. You can use a bonus action to try to get an uncanny insight about one humanoid you can see within 30 feet of you. Make a Wisdom(Insight) check contested by the target’s Charisma(Deception) check. If your check succeeds, you have advantage on attack rolls and ability checks against the target until the end of your next turn. Additionally you gain proficiency in the Investigation skill.