I have been playing the game for 4 years. My best role and my most enjoyable role is the ADCarry/Marksman. I've been playing Lucian since release, and I believe he is a dominating lane opponent. His burst which consists of using an ability and then using your passive is a frightening thing to trade against.

This guide was made on 12/2/2013 so Lucian is prone to changes that I may not acknowledge in this guide. I believe this build is the best way to maximize the efficiency on Lucian. The update history is located near the bottom.

Now lets relentlessly pursuit on to the guide!

For those of you who want to pick up on Lucian or already Lucian player who want to learn more than this guide is a great guide to it.

Lucian is a mobile ADC who uses his abilities to combo well with his passive "Lightslinger". He is a hit a run champion who combos his abilities with basic attacks in order to help him hit and then run. His high burst and a good amount of utility makes him one of the best AD Carries in the game.

Lucian is a also a very versatile and enjoyable champion to play so getting bored of him will not be a problem.

Lucian lacks cc so his best lane partners include: Leona, Taric, and Thresh.

PROS:
+Nice Range. Nice Burst.
+Mobile.
+Ult is great to use if you can't land autos.
+Crits work well on him due to his double attack on his passive.
+Dash over walls.
+Can play aggressive even without an aggressive support.

Cons:
-No CC at all.
-Q can be hard to land in some situations.
-Can't change direction of ult.
-W can also be a hard skillshot to land due to its slow speed and star pattern.

Greater Mark of Attack Damage Standard for AD Carries. This bumps your AD by a good amount which makes last hitting + trading a lot easier.

Greater Seal of Armor Standard for AD Carries. You need to survive the enemy AD hits so you run these.

Greater Glyph of Magic Resist Pretty standard for AD Carries also. Their supports are usually AP, but their team may consist of high AP damage carries. Take these so you can survive those.

Quintessence of Life Steal I love running 2 or 3 quintessences of life steal. This makes trading and sustaining so much easier. If they decide to trade, you can lifesteal it back up with some lifesteal quints.

Greater Quintessence of Attack Damage Adds some extra damage to your AD. I use this instead of another Lifesteal Quintessence because 2 Life Steal quintessences with his passive is enough Lifesteal. I also just enjoy addition flat damage.

Blade Weaving is great on Lucian. Since Lucian is based off using an ability and then following 2 basic attacks, Blade Weaving boosts that damage by a lot. Not only that, taking a point into the sub-portion of Blade Weaving which is Spell Weaving is also great on Lucian. Since some of Lucian's abilities scale off a small amount of AP, then the stacking spell power of Spell Weaving is a great damage boost on Lucian.

I do not take Recovery because you have 2 lifesteal quints as well as getting Bloodthirstier first. These extra lifesteal bonuses make the health regen useless while Enchanted Armor helps with defensive items.

The most used summoner spell in the game. Great for getting out of sticky situations.
Great summoner spell for surviving burst.
If you want the extra damage then go for ignite.

Lighslinger After using one of his abilities, Lucian's next auto attack within 6 seconds will strike twice. The second shot deals 50% of Lucian's AD based on level, but fully applies on-hit effects. Minions and monsters take full damage from the second shot. The second shot can critically strike.

Always utilize this passive. In most situations you must maximize your damage by using this passive every time you use an ability. This passive scales great with critical chance. You have the chance to deal a double critical hit which may quickly drop the enemy health bars. This passive contributes a lot to maximizing Lucian burst.

Piercing Light After a 0.35 second delay, Lucian fires a laser in the direction of the target enemy: physical damage to all enemies in a line. Minions take 75% damage. This is not a skillshot. You must click a target and Piercing Light will shot in a line from that Target

You should be prioritizing this ability. This ability provides a nice burst of damage and combining this with your passive will maximize your burst potential. This skill can be hard to land. You must have a target selected and then you will fire a straight line of piercing light from that target. At the same time, if you hit all 5 enemy champions then the teamfight potential from Lucian will be very high. A good description of the spell can be found here: Piercing Light Tutorial

Ardent Blaze Lucian fires a shot that explodes upon hitting an enemy or reaching the end of its path, damaging enemies in a cross pattern for % magic damage and % Physical Damage marking enemies hit for 6 seconds.If Lucian damages a marked target with his basic attacks or abilities, he gains a flat movement speed bonus for 2 seconds. This does not consume the mark.

This ability provides decent damage, but most importantly it applies good utility to make Lucian the "Hit and Run" type of champion. This skillshot blows up in a star formation and it also has a very slow firing speed so it can be hard to hit in some situations. You should be firing this ability and using basic attacks/the culling to peel for yourself. You can also combine this with your passive to maximize burst. You should be prioritizing this second.

Relentless PursuitLucian dashes a short distance and removes all slowing effects. Relentless Pursuit's cooldown resets if Lucian scores a kill or assist during The Culling.

This is also a great ability for chasing/running. It removes slows but not attack speed debuffs such as Wither. You can also use this ability to combo up with your passive. Be careful though. Do not use this ability to dash into a fight if you know there is no way of getting out. This does reset on kills/assists so dashing in to clean up fights is a great way to use this ability effectively.

The CullingLucian starts firing at Lucian's attack speed at the time of cast shots in the target direction for 3 seconds, each shot damaging the first enemy it hits for 25% bonus AD and 10% bonus AP. The amount of shots fired scales with his attack speed. The Culling is considered a channeled ability and it can be interrupted, but Lucian can move freely (including movement abilities) without interrupting it himself.

Reactivate The Culling to cancel the ability early.

The Culling deals triple damage to minions but not monsters.

This ability always has many misconceptions in the community. This ability feels like it does no damage, but it is great when you can't land autos in teamfights. Remember. When you start using the culling, you can't change the direction but you can cancel the ability. Use this ability in these ways:

When you are running and you can't land autos during teamfights. Either you're not in range or you're just too scared to get cc'd. Shoot out your Ardent Blaze, and press The Culling so you can still pull out damage from long range without the fear of getting cc'd. I cannot stress this enough. As an ADC, you should be prioritizing your autos to max out your damage instead of using your abilities. In Lucian's case, using your abilities is very good because you can utilize your passive, but do not use the culling when you can safely land your abilites/autos.

Securing a kill. If someone with 50 hp is far away from the range of Lucian, then fire the Culling to try to secure the kill.

DO NOT USE THIS ABILITY WHEN:

You can safely land your abilities/autos in teamfights. Using your autos/abilities will always pull out more damage than the Culling. Land autos if you can, don't start shooting the Culling until you can't safely land autos.

Don't use this ability in the middle of nowhere. You can't change directions, so do not waste this ability. If you start shooting it randomly then you WILL get cc'd and die.

I like this item on most AD Carries in the game. Nice attack speed. I don't prioritize attack speed on Lucian but this is pretty standard for an AD Carry.
The flat damage works well with Lucian's burst while the sustain from Life Steal is also beneficial to have in lane/team fights. This also helps increase early damage on the Culling.

Why take Bloodthirster before Trinity Force? Trinity Force is great and all, but it lacks the early game damage that you need to secure dragons + early team fights.

I love this item on Lucian. The phage helps Lucian become the "hit and run" type of carry. The zeal helps with a small attack speed/critical strike bonus and the Sheen helps with his style of using an ability then basic attacking for his passive proc. This item benefits Lucian a lot.
Lucian is a good at prioritizing Critical Strike. If they have a large tank line than Last Whisper is the more cost and damage effective. At the same time, if their team has little tanks than IE will shred through the whole enemy team. The double hit on his passive is a great combo that works with critical strikes. Not only that, but the damage bonus on Infinity Edge also benefits Lucian's burst. The 50% extra Critical Strike damage is also great for maximizing burst with your passive.
This item is situational, but it is currently more effective than Infinity Edge because of the high tank meta. If you need to go defensive after Infinity Edge then go defensive. If you are feeling confident in surviving then go for Last Whisper. The nice damage boost + Armor Penetration is great for Lucian's burst. I recently switched LW with IE, because of the current high tank meta. IE will do you no good vs the tanks that are all over your face and LW is a lot more effective vs large tanks, which exists a lot because of the current meta(ex. Mundo, Shyvana, Renekton). If the enemies are squishy then go for the IE first if you have the money to invest in it, otherwise stick with Last Whipser.
Defensive items are situational. Like I said if you need to go defensive after Infinity Edge then go defensive. This item can be game changing. If you need to survive burst then the extra armor and magic resist can easily save your life. The passive on this item is also very beneficial to have. The second life can easily change a team fight around. If you feel like you can survive fights without worrying then go for a different defensive item.
Mercurial Scimitar is great if they have a lot of CC on their team. You can clense off a stun or a slow in order to peal for yourself. I also like this item because it builds from Quicsilver Sash You can leave it at QSS and then go into another damage item.
Frozen Mallet is great if they have a lot of champions who can easily get into the backline. The slow on this ability can make Lucian's running potential so much better. This item also works well with your passive.
There are more defensive items but these are generally the best ones.

BAD:

Vayne can easily tumble away from your locked in Piercing Light and she can also dodge your Ambient Blaze. She can also easily stealth/tumble to avoid the Culling.

A skill dependent matchup although Ezreal should be easy to beat if you dodge skillshots. Ezreal can survive your burst, but he can also match it. He can easily Arcane Shift into you while comboing his Mistic Shots + Auto Attacks to match Lucian's Burst. Ezreal is leaning on the side of being beat by Lucian easily, just because of how much damage Lucian has over Ezreal.

Draaaaaven. He can also match your burst by simply using his auto attacks. He can also cancel the Culling by throwing his axes to make you "stand aside".

Good old Soraka. She can silence you when she ults, but she can also counteract your burst by using her heal to gain more armor for herself and her teammates.

Annie has a lot of CC and because you can only remove slows, you get stunned and then instantly busted into oblivion.

GOOD:

Varus relies on Auto Attacks and then followed by his abilities to deal burst. Lucian on the other hand has very quick burst that can easily kill Varus faster than he can get his burst down. Not only that but you can remove Varus's slow.

Jinx cannot deal with burst and Lucian has a lot of burst.

Again, a very skill dependent matchup. If you can stand by minions to avoid Ezreal burst then you can easily win. Ezreal is leaning on the side of being beat by Lucian easily, just because of how much damage Lucian has over Ezreal.

Pretty simple here. Lucian can avoid slows so that counters Ashe's kiting potential from her slows.

Lucian can easily remove Thresh's slow and Lucian also is very mad at Thresh because he stole Lucian's wife.

A very great combo with Lucian. Her CC and her burst combined with Lucian burst is always enough damage to instantly burst their carries. If they are stunned then they cannot dodge your Piercing Light and Ambient Glaze. Even with the Annie nerfs, the small stun will always be a great partner to Lucian.

Armor shred works very well with Lucian. Taric is also generally doing very well in Pre-Season 4, because his potential to get armor items helps tank damage while also making Taric's damage do well.

An aggressive support that can cc enemy targets so they can't avoid Lucian's abilities. Leona also pairs well with aggressive AD Carries like Lucian.

A less straight up aggressive support, but has a lot of CC potential that helps Lucian's burst.

For the look of the guide, I do not enjoy putting videos in the middle of each different section so I have one section dedicated to helpful videos.

This is the Lucian champion spotlight made by Riot Games and it does a good job of describing Lucian's abilities.
Play Video
Great Guide of giving in-detail descriptions of Lucian
Play Video
Great Guide to ADC Laning
Play Video
Great Guide to ADC Teamfighting
Play Video

EDIT LIST:
12/4/2013: Changed some guide formatting around as well as fixed some pesky typos.

12/6/2013: Added the Update History Chapter. Fixed the random sentence blank on the Masteries section. Also explained the Mastery chapter in a more detailed and in-depth way. Thanks to the people in the Guide Discussion for pointing the mistake out.

12/8/2013: Typos as well as changed the titles of some chapters.

1/21/2014: Acknowledged the changes that have happened to Lucian after this guide had been made in terms of numbers and ability descriptions. I also made sections a lot more clearer, and I went in depth about why I took some items more than others. Also acknowledged some support champion changes.

2/22/2014: Switched the build around. LW > IE, because of the current tank meta. You can read this in the core build section under the Last Whipser and Infinity Edge icons.Updated introduction and the runes a little bit too. Also added another build called "squishy enemy team build". Changed title also. This was done in patch 4.2 which is the current patch at this time.

2/26/2014: I got Diamond today guys :D. Replaced Platinum with Diamond.

Lucian is a very strong and versatile AD Carry. I love his hit and run style while still pulling out a lot of damage. He is a great AD Carry to run when the enemy team doesn't have much CC. My favorite skin on this champion is just the default one. I like the long blazer style look and I also enjoy the Auto Attack sound/animation.

I am currently a Diamond 5 player in NA that has played this game for about 3 years. I have always enjoyed playing the role of AD Carry and I love helping other players improve. Here is a link to my Mobafire Profile: My Mobafire Profile. If you want to check out my other guides then visit my profile!

And here is a link to my LoLking Profile: My LoLking Profile.

Am I missing something? Shoot me an message on Mobafire and I will read it as soon and I will respond. Just label the title as "A problem in ___ Build." Also if you notice any typos/grammar issues then do the same.

If you like the guide then hit the upvote button and comment if you wish! This guide will continuously be updated. Happy Season 4 everybody!

Thanks for reading and have a wonderful time climbing the solo queue ladder!