Welcome to my Lux guide.

I play Lux for quite some time and I hope i can help you to achieve your goal:

-To become a good Lux, The Lady of Luminosity.

Before you decide to play a champion, you should ask yourself a question:

Who Is?

Well, Lux is a long-range AP nuker.
She has a mass of CC a great finisher ultimate and a decent shield to keep your team alive.
A Great MID Champion but mostly played wrong,ends up as a feeder and makes Lux look bad.
I'l show you HOW NOT to become a feeder but a supercarry and i even decided to make a support part.

PROS:
-Big Range
-Dominant in MID (in most cases)
-****load of CC
-Protects whole team with Prismatic Barrier (if you can hit the whole team)
-So easy to poke that it is not even fair
-Lots of Fun

CONS:
-Early Mana problems
-Skillshot champion (if you have problems with skillshots you might have a problem)
-NO Escape Abilities
-You WILL get Focused

THE AP Lux RUNES:

Greater Mark of Magic Penetration - This combined with Sorcerer's Shoes should crack open at least 80% of enemy MR (unless they have MR runes or items)
Greater Seal of Replenishment - We take these to regenerate our Mana faster. We take them over Greater Seal of Scaling Mana Regeneration because they give because Greater Seal of Replenishment work better early game and there should be no Mana problems late game due to Tear of the Goddess.
Greater Glyph of Ability Power - We boost our Damage Output up a bit with these.
Greater Quintessence of Health - Without these you are EXTREMELY paper!
You need them in order to be able to sustain because Lux starts the game with around 424HP, that should be about 2-3 Pillar of Flame and you are DEAD!
If you want to play this build get this runes.

ALTERNATIVES:
Greater Mark of Ability Power
Greater Seal of Scaling Mana Regeneration
Greater Glyph of Cooldown Reduction
Greater Glyph of Magic Penetration
Greater Glyph of Scaling Cooldown Reduction
Greater Quintessence of Ability Power
Greater Quintessence of Magic Penetration


THE SUPPORT Lux RUNES:

Greater Seal of Ability Power - We take these because Greater Mark of Magic Penetration has no effect on Prismatic Barrier and as a support you should PROTECT THE CARRY!
Greater Seal of Replenishment - You poke your Foes you lose your Mana; We need to regenerate Mana to keep our Spells Flowin'.
Greater Glyph of Cooldown Reduction - You want to keep your carry shielded as long as you can whenever he needs it; Lux has some CD's so we take this to make them shorter.
Greater Quintessence of Health - You shouldn't leave your base with 424HP. Take these.

ALTERNATIVES:
Greater Mark of Magic Penetration
Greater Seal of Scaling Mana Regeneration
Greater Glyph of Magic Penetration
Greater Glyph of Scaling Cooldown Reduction
Greater Glyph of Ability Power
Greater Quintessence of Ability Power
Greater Quintessence of Magic Penetration

There are 2 ways of setting up masteries for Lux.

1.The AP Lux - The Damage dealer, the carry, the REAL Lux.

We take 21/0/9 for AP Lux.

OFFENSE TREE:

Mental Force - More AP for more damage on your spells.
Sorcery - CDR is always nice for AP carry and you can poke more often in early game.
Arcane Knowledge - A MUST! You blow holes in your enemies with this!
Havoc - Just some more DAMAGE on everything.
Blast - More AP = More DAMAGE.
Archmage - Imo this is a must on every AP carry, it works like a tiny passive of Rabadon's Deathcap.
Executioner - MY FAVORITE! No more calculations on your Finales Funkeln! Just blow a hole in that Karthus!

UTILITY TREE:

Summoner's Insight - 15 sec off Flash and it also cuts off some cast time on Teleport.
Expanded Mind - More Mana for your pokes and Archangel Staff.
Good Hands - Might seem kinda noob but when enemies are making the last push with you down your team WILL need you alive.
Meditation - Mana reg. is a good thing for a poker like you.
Runic Affinity - A good jungler will let youThe Golem Buff;That will let you poke all day long with lower CD and no mana problems.You want that to last longer don't you?


2.Support Lux - Alternative way of playing Lux is as a Support.

We play 9/0/21 on a support Lux.

OFFENSE TREE:

Mental Force - Support or not, you should deal some damage late game.
Sorcery - CD on Prismatic Barrier and your CC makes you a supporter of some kind.
Arcane Knowledge - You must poke as hard as you can early game to help your carry farm in peace or make some damage.


UTILITY TREE:

Summoner's Insight - Makes Clairvoyance work longer.
Good Hands - With Flash and Light Binding on CD while warding around the map you WILL LIKELY DIE! Make it last shorter.
Expanded Mind - More mana = You are less OOM. OOM Lux = Useless Lux.
Meditation - You need mana reg. to keep your mana flowing and spam your Prismatic Barrier.
Scout - You are support, you lay down Sight ward and if they have bigger sight range you know more about map activity.
Greed - We max this because you must not farm as a support and you need as much GOLD as you can get.
Awareness - I guess you have to compensate the XP u lose warding around the map.
Intelligence - More CDR = More spam of spells.
Mastermind - This is very nice! Flash is always nice to have ready and also there is more frequent Clairvoyance for map control.

GOOD SPELLS:

Teleport - Play it as:AP Carry
Good thing to get out and back to lane quickly! You can help other lanes and position yourself by teleporting on a Sight Ward.
Flash - Play it as:AP Carry,Support
Only and remember ONLY way for you to escape a gank!
You can also use it to position yourself in a teamfight.
Clairvoyance - Play it as:Support
Supports take this for map control. Always!

VIABLE SPELLS:

Heal - Play it as:Support
If your carry asks you to get this due to Lux's lack of healing abilities take it instead of Flash, always have your Clairvoyance!
Ignite - Play it as:AP Carry
If your team lacks Ignite you should take it instead of Teleport.
Clarity - Play it as:AP Carry
If you're a fan of this take it instead of Teleport;but keep in mind Clarity is plain bad late game and you will have a ****load of Mana due to Tear of the Goddess.
Exhaust - Play it as:AP Carry
Really ****py summoner spell pick but if your dumbass team has no Exhaust pick it and use it well.

Illumination

If you hit your enemy with your offensive spells they will leave a MARK on your target(A Golden Bulb).
You can land your autoattack on the marked enemy and make bulb pop dealing some damage.

This deals A LOT of Early Game Damage!
You can also hit marked enemy with Finales Funkeln as it will also trigger the Mark.
Do not rely on it later as it becomes useless late in game.


Light Binding

This is a Skillshot snare that keeps flowing after it hits target and makes its effects 50% weaker on next one.
This is the spell that makes your enemies sit while you snowball em' to death with Illumination, Lucent Singularity and Finales Funkeln*.
This also saves you from GANKERS like Udyr, Skarner and Rammus.


Prismatic Barrier

A good Lux player knows how to hit his entire team with this and keep them safe.
It can also save you or your mate from that nasty Ignite.


Lucent Singularity

The poke tool!
Land your Light Binding first for most effective results.
You can use this without Light Binding as it has it's own slow so your enemy cant walk out of it that easy.
It is also a good slow in teamfights so don't pop it straight away.


Finales Funkeln
Play Video /league-of-legends/summoner-spell/clairvoyance-13 1300 DAMAGE,********!!1!





*Combo Section for more details.

You probably figured out that Lux has some really neat combos.
This is where i show the most important ones.
I made up some names for them!

1. Quickblast (Kill Combo)

Light Binding - Throw Lucent Singularity - Finales Funkeln - Shoot Lucent Singularity

In my eyes this is the most effective Lux combo.
You snare them with Light Binding then throw your Lucent Singularity onto then (you do not pop it yet!) then you follow up with Finales Funkeln (that will be a sure hit because the target is snared and slowed) that will trigger the Illumination mark and in the end you pop your Lucent Singularity to finish the poor bastard ^.^

2. Simple Poke (Harass Combo)

Light Binding - Lucent Singularity

Hit the target with Light Binding and simply detonate your Lucent Singularity.

3.Advanced Poke (Harass Combo)

Light Binding - Throw Lucent Singularity - Illumination - Detonate Lucent Singularity - Illumination (If you have time)

Snare the guy, make your Lucent Singularity ready by throwing it beneath the guy, autoattack him to proc Illumination, detonate your Lucent Singularity, proc Illuminate once more.
This will blow a HUGE chunk of HP in early game.

THE AP LUX:

START ITEMS:

Amplifying Tome and 1 Health Potion - We take this in most of cases for more AP/efficient poke.

Boots and 3 Health Potion - We take this when we are sure that we will have to move a lot, dodge skillshots that is(ex. Lay Waste, Noxious Blast, Arcanopulse...).

Doran's Ring - If you're a newbie take Doran's and follow the rest of the guide.

MORE ITEMS:

Boots - Make them next so you can perform your Advanced Poke Combo easier.

Tear of the Goddess - Let's kill that Mana problem. Sooner you get this the better it gets as you get more max. Mana for every spell you cast so try to spam spells as hard as you can. If you do it your late game Archangel Staff will turn you into a monster.

Mejai's Soulstealer - Many people dislike this item. They say "If you die you lose all your stacks"! This is what Lux is all about... Positioning! You have massive range, just stay behind,spam spells , get kills or at least assists - your offtank will defend you.
This is a risky item but champions like Lux, Katarina and LeBlanc shouldn't have problems getting kills and maintain their Mejai's Soulstealer.

Sorcerer's Shoes - Many people grab Ionian Boots of Lucidity thinking that they will have Finales Funkeln available every 24 secs. True... But a bad idea. Why? Do you like a strong ultimate every 32 secs or a strong poke every 24 secs? Your poke is your Lucent Singularity not your Finales Funkeln. Let this boots go and take Sorcerer's Shoes!

Rabadon's Deathcap - Now you have a powerhouse of AP ready to rock! Nothing more to say about this item than that it is a must on every mage.

Rylai's Crystal Scepter - We take this for it's stats. We get a big chunk of HP and AP + your Finales Funkeln can slow now. Make it Count!

Void Staff - Once you start kickin' *** around Summoner's Rift your foes will make Fon's and Banshee's Veils. Take this and crack their MR.

Archangel Staff - BEASTMODE Time!1!1! Remember that Tear of the Goddess from the start? Well your Mana has grown to intense levels and your Archangel's Staff just lifted your AP over 1000. That is the milestone your enemies WILL NOT forget!


VIABLE ITEMS:

Do not replace your core items unless your Mejai really failed.
Take one of these if you have a worthless Mejai

Zhonya's Hourglass - If you are still getting focused the most definitely get this and DO NOT FORGET to activate it when they rush on you!

Lich Bane - Late game you will hit a lot of damage with a single autoattack.


SUPPORT Lux ITEMS:

You are SUPPORT!
You buy this items only when you have spare gold!
Otherwise just ward, ward, ward and ward!

If you have problems warding please check out the best guide on MOBAFIRE - Panglot's Warding Helper (http://www.mobafire.com/league-of-legends/build/warding-helper-more-than-your-eyes-can-see-54337).
Panglot's guide helped me A LOT and i have a need to tell more people about this amazing guide!

Faerie Charm, 3 Sight Wards and 2 Health Potion - Basic support set. You rush Philosopher's Stone for GOLD INCOME!

Philosopher's Stone - Your Mana regen item and your GOLD INCOME.

Boots - Take them next for your combos and running away from their JUNGLER!

Kage's Lucky Pick - Some AP and more GOLD for ya'.

Ionian Boots of Lucidity - This is the time for CD boots! You must have your Prismatic Barrier and Light Binding ready to defend your carry from Junglers and enemy carry.

Rod of Ages - We make RoA over Rylai because Catalyst the Protector benefits support champions really well. More sustain = More Carry Babysittin'.

Shurelya's Battlesong - Nice Active, also we build it straight away from our Philosopher's Stone.

Rabadon's Deathcap- If you somehow manage to earn this much GOLD your team just got themselves another AP Carry.

Will of the Ancients - Aura will benefit the rest of the team, you deal damage now but it doesn't mean you don't have to do anything to support the team.

One Place in your Inventory must be open for Wards!

Thank You for reading my Lux guide!

I hope i helped you and i wish you Good Luck!