Peerless Skill is a Bard feature gained at level 14 in the 2024 SRD. When you make an ability check or attack roll and fail, you can expend one use of Bardic Inspiration; roll the Bardic Inspiration die, and add the number rolled to the d20, potentially turning a failure into a success.
When you make an ability check or attack roll and fail, you can expend one use of Bardic Inspiration; roll the Bardic Inspiration die, and add the number rolled to the d20, potentially turning a failure into a success. On a failure, the Bardic Inspiration isn't expended.