Hey Guys!
This is already my second Guide :)
My first is about Janna. You can find it here: The Swirling Firestorm.
I am from Germany, only using my English learned in school so i cannot promise all the words and grammar is the best.
Actually I am Silver-League and maining ADC. With favourite Lucian :).

so thanks for Reading and have fun.

For the Runes I use Standard ADC runes. That means:
9x Greater Mark of Attack Damage
9x Greater Seal of Armor
9x Greater Glyph of Scaling Magic Resist
3x Greater Quintessence of Life Steal

At the End there are this values:
+9 Armor
+4,5 Lifesteal Bonus
+27 Magicresist at LvL 18
+8,5 DMG

You can also try to change the dmg runes into armorpen or attackspeed. But i prefer the DMG for lasthitting.

Masteries are classic 21/9/0 but I have bit difference between Caster ADC and AutoAttack ADC.
You can see the Page above.

My Item build change above months, patches and my experience showed me that this build is the best for Lucian:
Starting with Dorans Blade, Healing Potion, Yellow Trinket.
Rush:
Infity Edge, Brutalizer, Last Whisper and Ionian Boots.
Go on with Essence Reaver and then finish the Brutalizer to the Ghostblade.
As Last Item you can build The Bloodthirster, Iceborn Gauntlet or Banshee's Veil.

Pros:

In my opinion Lucian is easy to learn after some games. You can play him against lot other ADCs and with every support.

Cons:

Ultimate is hard to handle

Like all the other ADCs.
You are the Carry. Stand in the Back and when your team engages follow. But as Lucian you also have a good duelling potential against low targets.

Double Shot.
As lucian you dont need lot attack speed. With this BUild you get 40% Cooldownreduction to use your speels as often as you can. So you can proc you Passive very often.

Farming is Very Easy with the double shot, the Qs Aoe-Line and the Ultimates Extradamage to minions.

Thank you for reading this Guide.

Hope you read my Janna Guide too.

See you :)