Dungeons & Dragons 5e Element 133 Class Feature: Retaliation

What doesn't kill you makes you stronger. This is the creed of all bruisers and you know it well. When a creature deals melee piercing, slashing, or bludgeoning damage to you, you can use that pain to fuel your combat prowess. On your next turn, as a bonus action, you can deal additional damage on your next successful melee attack equal to half the total damage that creature delt to you. For example, if an opponent rolls a 12 on their greatsword strike and adds 4 due to their Strength modifier, you can deal 8 additional damage with this feature, regardless of resistances. This damage can only apply to the target that dealt that damage to you. You can use this feature a number of times equal to your Constitution modifier and you regain all expanded uses once you finish a long rest.