Hello my name is NDarKnight and i hope this guide will help you to win games i play with this guide and its good guide try it out. You should avoid playing against pyke you can see in threaths why you should avoid him he just gone invisible press Q throw you back and their mid laner kills you easy and if pyke have ult you are done. Anyway i hope you like the guide.

Most of Lux player take Ignite and Flash but i prefer using Barrier cause on early game if you get low hp or zed used ulti on you and you see if you take Barrier you will survive so its pretty cool to have it, so using Barrier isnt that bad. You can go Ignite too but you cant outplay them under your turret when they try to dive and you use Barrier and use Light Binding and Lucent Singularity, your Lucent Singularity will slow them and Q will root them so its ez to ouplay enemy while they dive when you have Barrier so i would recommend using Barrier. If you take Barrier use it smartly.

About lux items i dont have to say allot its classic Lost Chapter it restores your mana gives you bonus mana and gives you AP so its great item for start after build it to Luden's Tempest which will grant you more AP and more mana and cooldown reduction after that take rabbadon (if you can) you need to be feeded to buy rabadon if you are not feeded go buy other stuff then buy rabbadon for last item take zhonya if you need it it depends on matchup you will know when to use it, take Void Staff as i said its classic items nothing special just get feeded and win not so hard with lux.

Illumination-passive
Lux's damaging spells charge the target with energy for 6 seconds. Lux's next attack ignites the energy, dealing 18-190 (at levels 1-18) (+20% of ability power) magic damage to the target.
Light binding-Q
Range: 1000
Cooldown: 10 Cost: 40 / 45 / 50 / 55 / 60
Lux releases a sphere of light that immobilizes and deals 70 / 115 / 160 / 205 / 250 (+70% of ability power) magic damage to up to two enemy units for 2 seconds. Its pretty cool combined with Final Spark and Lucent Singularity. If have 2 items and you go on squishy champ like adc or not tank supp or their not tank jg just do combo and they are dead.
Prismatic barrier-W
Range: 1000
Cooldown: 14 / 13 / 12 / 11 / 10 Cost: 60
Lux throws her wand to a target location and back, bending the light around herself and any friendly Champions it touches, protecting them from 50 / 65 / 80 / 95 / 110 (+20% of ability power) damage for 3 seconds. The shield value is doubled upon returning to Lux.
Lucent singularity-E
Range: 1100
Cooldown: 10 / 9.5 / 9 / 8.5 / 8 Cost: 70 / 80 / 90 / 100 / 110
Fires an anomaly of twisted light to an area, which slows nearby enemies by 25 / 30 / 35 / 40 / 45% and .25 seconds while out of the zone. Zone lasts 5 seconds. Lux can detonate it to deal 60 / 105 / 150 / 195 / 240 (+60% of ability power) magic damage to enemies in the area of effect. Enemies damaged by the singularity are slowed by 20 / 24 / 28 / 32 / 36% for .25 seconds. Reveals the area while in flight and while stopped. Displays a cooldown timer until the singularity automatically detonates. Can be re-cast in flight to detonate on arrival.
Final spark-R
Range: 3000
Cooldown: 80 / 65 / 50 Cost: 100
After gathering energy for a half second, Lux fires a beam of light that deals 300 / 400 / 500 (+75% of ability power) damage to all targets in the area and reveals it. It ignites and refreshes Lux's Illumination debuff if it hits enemies already afflicted.
If an enemy champion dies within 1.75 seconds of being hit by Final Spark, 30 / 40 / 50% of its remaining cooldown is refunded. Dont use it if you dont have sure kill or at least save your teemate or if enemy is rooted and you want to get his hp to low so you or your teemate can kill him easy.

Sorcery
Arcane comet
Arcane Comet is my choice for Lux. When off CD, whenever you damage an enemy with an ability a comet will fly over from you to them and hit them to deal extra damage. This is good on Lux, she relies on her abilities to do damage. Due to this, she is able to consistently pop Comet both in skirmishes and while poking the enemy with her Light Binding and Lucent Singularity . As her Lucent Singularity a slow, Comet is almost 100% sure to hit the enemy they cant escape your comet cause slow and you stop them with your Light Binding
Manaflow band
Manaflow Band recovers you mana which is good at early game Lux dont have alot mana at start but it have cooldown (15 sec), upon earning 250 mana, Manaflow band restores 1% of your missing mana. With Manaflow Band you can get extra mana in early game which is cool.
Transcendence
Transcendence grants you CDR when you reach lvl 10 and excess CDR becomes AP or AD (Adaptive).Its gives you more dmg to poke enemy, because more you have CDR more damage you deal.
Gathering Storm
Gathering Storm After 10 minutes you get 5 AD and for every additional 10 minutes this value gets raised pretty high. This rune is good for ad in lategame. This rune scales perfect and you´ll do more damage the longer the game goes on and for adc´s its pretty important to do a lot of damage lategame.
Domination
Eyeball collection
PASSIVE: Collect 2 Eyeballs from champion kills and 1 Eyeball from champion assists and ward Damage rating takedowns, up to 20. Gain 1 Ability Power or 0.6 Attack Damage (Adaptive) per Eyeball, up to 20 Ability Power and 12 Attack Damage. Eyeball Collection has a 10 second assist timer.
Completing your collection awards an additional 10 Ability Power or 6 Attack Damage (Adaptive). Eyeball collection is awesome rune it will grant you bonus damage and it is really usefull cause you cant do much damage without items so this is great on lux so i recommend it for you too.
Relentless hunter
PASSIVE: Gain 8 (+ 8 per Bounty Hunter stack) out-of-combat Movement speed icon movement speed. Earn a Bounty Hunter stack for champion Damage rating takedowns, up to one per unique enemy champion. Relentless hunter on lux is great at start cause when you hit him with spell you need to take a chance and hit him but if you dont have boots dont count on that thats why i take relentless hunter.

PROS:
+Do allot damage with few items.
+can easy gank other lanes.
+CC lockdown.
+Low CDR to ult.
+Works well with any jungler.
CONS:
-If you miss combo you are easy target until your combo is ready again.
-No escapes (no dash no invisible cant escape easy target to jungler).
-All spells are skillshot so....
-Weak against tanks.
-easy to counter.

I would like to talk how to beat lux, if you dont know how to beat lux you wont know how to protect yourself playing lux.Save your mobility spells to dodge an incoming Light Binding as hitting it means she can fully combo you.
A lot of Lux's damage comes from her Illumination. If you get tagged by Lucent Singularityor Light Binding, step back for 6 secs so she can't proc the extra damage.
Lux's Prismatic Barrier grants twice as much shield when returning to her.
If Lux hits a target with Final Spark that dies within 1.75 secs of being hit, she will get a partial CD refund, enabling her to use her ult again shortly after.
Her big power spike is really upon hitting lvl 6 with Final Spark
. 100 - 0 potential if she gets you with a Light Binding Her big item spike is at 1.5 items: Luden's Tempest or Archangel's Staff + Oblivion Orb + Sorcerer's Shoes . If you don't have MR and get Q'd, RIP.
She lacks mobility and has limited peel. If she uses Light Binding
in lane, that's the window to engage on her if you have gap close or jungler.
She struggles to clear waves early as
Lucent Singularity isn't strong enough. Pushing her in is good. Anyway i hope you liked the guide try it out and i hope it will help you, enjoy.