Active: Gangplank places a powder keg that can be attacked by himself or his enemies.
If Gangplank destroys a keg, it explodes in an AoE blast that slows enemies by 40 / 50 / 60 / 70 / 80 % for 2 seconds and spreads the damage of the attack to all nearby enemies. Other casks within the zone will chain explode. Explosions ignore 40% of their targets' armor, and enemy champions take 60 / 90 / 120 / 150 / 180 bonus physical damage.
If an enemy destroys the cask, it defuses the explosion and grants gold.