League of Legends Reforged Rune: First Strike

Dealing damage to an enemy champion within the first 0.25 seconds of champion combat, grants 10 gold and First Strike for 3 seconds, causing all of your damage dealt against champions to deal 7% bonus true damage. Afterwards, you are granted [50% for Melee | 35% for Ranged] of all bonus damage dealt within the duration as gold.

First Strike will be placed on cooldown after being struck by an enemy champion before you strike them.

Cooldown: 25−15 seconds (depending on level)