Mark of the Slayer

Slayer Technique: 3rd level You immediately learn if the target of your Ranger's Quarry feature has any damage immunities, resistances, or vulnerabilities and what they are. Additionally, the first time you hit the target of your Ranger's Quarry feature with a weapon attack each turn, it takes extra damage equal to your Ranger's Quarry Damage Die. The damage is of the same type as the weapon's damage.

Granted by Slayer Technique at 3rd level.