Gangplank + Ethereal Weapon

Each barrel chain adds 35% damage, scaling exponentially.

Barrels have 0 move speed, so it's a flat 33%+ damage boost.

Mystic Punch enables infinite Q; Dusk and Dawn lets Q proc Sheen, so it's perfect for players who can't barrel-chain — just max Q.

80% of GP's damage comes from barrels (E), which the system treats as zero-MS enemy targets. When firing barrels, he gains MS and slows enemies, opening up a huge MS gap and locking E into its 40% damage cap. Post-explosion bonus MS keeps the gap up for sustained huge damage.

Back to Basics massively boosts barrel damage for one-shot kills — barrels have innate 40% armor pen, so they hurt tanks too. Need solid barrel-chain skill; watch positioning vs long-range poke.