Lucian

Bottom

Stay Dead

Ramping damage, lifesteal/sustain, and scaling ramp damage.

Precision

Improved attacks and sustained damage

Press the Attack

Attacking a champion 3 times will expose them, dealing bonus damage and causing them to take more damage from all sources for 6 seconds.
Overheal

Excess healing on you becomes a shield.
Legend: Bloodline

Takedowns on enemies grant permanent Lifesteal.
Coup De Grace

Deal 7% more damage to low health champions. Gain AD/AP after kills or assists.

Sorcery

9% attack speed, 10 ability power or 6 attack damage

Celerity

Gain 3% extra MS. Gain extra AP or AD, based on your bonus MS, Adaptive.
Gathering Storm

Gain increasing amounts of AD or AP, Adaptive over the course of the game.

WhyPress the Attack

Press the Attack's exposure damage synergizes incredibly well with BotRK + Black Cleaver + [R] shredding even the tankiest champions.

WhyOverheal

Overheal is a great rune for topping off your heal to sustain chip damage from the enemy, and synergizes well with the Life Steal from BotRK and Bloodline.

WhyLegend: Bloodline

More Life Steal means longer trades equalling Lucian gets off more Passive procs and Press the Attack damage.

WhyCoup De Grace

Coup De Grace is a great rune for finishing of the last bit of health on champions you have shredded with Black Cleaver and Press the Attack.

WhyCelerity

Lucian's low auto-attack range makes him vulnerable when looking to attack. Celerity's bonus Movement Speed helps you to kite around your max range for more safety and mobility.

WhyGathering Storm

Gathering Storm is your late game insurance policy. Paired with Press the Attack, your late game single target dueling damage will be massive.