This is a Rage Power option.
- When you take damage from a creature that is within 2 meters of you during your rage, you can use your reaction to make a melee weapon attack against that creature.
- Additionally, when you take damage from an attack within 10 meters, you can force the attacker to make a Dexterity(Acrobatics) contested roll against a DL of 10 + your Constitution modifier + your Proficiency bonus. On a failure you deal 1 piercing damage, 1d4 poison damage and the target is poisoned until the end of its next turn.
- You have a disadvantage on attack rolls and ability checks.