Lucian vs Yasuo

Weave an auto between each spell: Lightslinger (passive) turns it into a double shot, and each shot that hits lowers the cooldown of Relentless Pursuit (E).

Attack right after an ally's heal or shield, or a nearby enemy getting immobilized: Lightslinger (passive) then empowers your next 2 autos.

Cast The Culling (R) on a target your team has immobilized: each shot hits the first enemy in its path, and you can use Relentless Pursuit (E) while firing.

Look for trades and kills early on: Lucian is strongest early, and his impact drops once the other marksmen have their items.

Hit him with a cheap attack to trigger the Way of the Wanderer (passive) shield, then start the real trade: otherwise, it absorbs your best damage.

If you have projectiles, save them for after Wind Wall (W): it blocks them all for 4 seconds, on a 25 to 17 second cooldown. Other spells go through it.

Don't stand right behind your minions: each one gives him a target for Sweeping Blade (E), and he gets closer to you with every dash.

Get out of the line of his whirlwind, the third Steel Tempest (Q): without a knock-up, he can't cast Last Breath (R).

Judge his threat by his crit items more than his level: Way of the Wanderer (passive) raises his critical strike chance, so each crit item does more for him.