EDIT #1: Explained Core/Lategame better.
EDIT #2: Added to Foreword.

When I play Lux, I play mid. Ive tried solotop, and while it is still doable, the feel and play is very different to me ( IE, I had my *** handed to me )

Also, I play Lux as a Carry. Perhaps not fullblown because of not focusing on kills, but the wards I buy ( not listed ) are for use in my lane to keep me alive.

Build Explanations:

Build #1
Early kills, or assist from jungler pushes you into an advantage and you take it to late game. A match where you are very likely to carry with a full stack of Mejai's; and many Assists which gives you later many kills. More on this later

Build #2
Its not your game. Either their mid or jungle ( or both! ) got an early advantage on you, and you know that a Mejai's is not going to be a feasible choice for you this game. In fact, you being a carry isnt on your mind; simple survival is.

I am a newer Lux player, but I have had much success with this build and build style, and thought I would post it on Moba for the review of my peers.

If you downvote me, please give feedback as to why.
If you give feedback, please have tried my build ( meaning play her and be good enough to do Build #1 ) at least once.

In other words -
If you cannot be successful enough with Lux to do Build #1; you are not qualified to give an opinion of it.

I run HP, MPen, Mana/18, AP/18
The larger health pool, combined with the Health Regen start, gives an advantage over a full AP/AD champion. If you can make them go B just once, you have an advantage of usually at least one level, that will only grow larger.

Standard AP Caster 9/0/21; making sure to grab the improved point in Clarity.


TL;DR - I have had much success with Clarity, enough to warrant use over Ignite or Teleport. If you disagree, to each their own.

Why I take Clarity over Teleport/Ignite/other spells:
I enjoy the added aggresiveness that Clarity allows me, enabling me to drop E more often to push harder for the enemy to either B or get killed.
In a good match my jungle will either cover mid long enough for me to return and buy my first few items ( Philo > All else for increased Gold income // if you are getting zoned enough to need boots first, the extra income is a help because you arent earning G from last hits ) or I will stay in lane long enough for it to come back on its own and be ready. Lategame, Clarity can be a huge help when everyone is low on mana from a gank etc and a teamfight is about to go down.

R > E > Q > W

In a good match, I will not train W until lategame when teamfights are happening. The reason for this is I will not waste the mana on so little return anyways, and the increased damage on E and Q allow me better odds of zoning my enemy or getting their kill.

Ah, my item build. The reason I am making this guide in the first place, and possibly the only part someone wants to read when they look at my guide.

It goes as follows, in my head:
Regrowth Pendant + 1 Health Potion
Philosopher's Stone
Boots of Speed
Amplifying Tome / Mejai's Soulstealer ( 1235 ) OR Needlessly Large Rod
Mejai's Soulstealer
Ionian Boots of Lucidity
Rabadon's Deathcap
Zhonya's Hourglass

Core Build: Philo, Boots, Mejai's, Rabadon's, Zhonya's
Core Build: 9785 or so.

Choices from here, as required by the game:
Lich Bane
Will of the Ancients
Void Staff
Eleisa's Miracle ( Not recommended, but a choice nonetheless )
Guardian Angel
Banshee's Veil

If my game is going well enough that I finish my core, I am usually sitting on 15-20 stacks on my Mejai's. If the chance of me dying is low ( Ive gotten good at running and using all skills to aid my escape ) Ill usually go with a Lich Bane to get all of my AP added onto my Auto Attack.

Yes, you read that right. It is seriously that vicious of a combo, to hit someone in the face with a laser and a stun, and then finish them off with an AutoAttack hitting for upwards of 700 damage.

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Lategame: At this point, sell Philo and get one last item from the situational list. If I am completely rolling the enemy team, I will usually go with Void Staff, to combat the MR that they have. If I need more survivability, I will usually go with Guardian Angel just for that chance of escaping and maintaining my stacks.

The key to Lux, with this build.
Be Aggressive, but smart.

Mid is your domain. Push it and own it.
The range Lux can fire her E, without moving, is huge.

If you can time it to get at least one minion last hit, the cast is worth it.
When you get good enough to time the last hits *AND* hit your mid opponent?

You will begin getting the first bloods, before anyone expects it.

Hit them with E. Hell, hit them with Q if they try to close ( overzealous Morgana's and Akali's, im looking at you. )
( I kill both in mid, btw. )

Whittle your opponent down. Get to 6. Begin farming with Ult, trying to get enemies health down.

Many people will tell you to time your Ult, saving it for a snipe.
I say screw that. Very often, the first 10-15 stacks of my Mejai's are from assists and very often a kill or two.

Think about that for a moment.
Your teammates get the majority of that gold, enabling them to be stronger. But you are gaining Gold and AP, making you stronger as well.

By the time you finish your build? You can stand on par with your teammates, with less kills. This makes your team stronger, overall.

Lategame is when I begin raking in my kills. If a teamfight is about to happen? I will open with my laser on the entire enemy team, weakening them and making our victory more likely.

I will then focus on stunning enemies in place with Q when they get too close, or dropping the E on grouped up enemies when they are bunched up or fighting.

Remember that you autoattack for more damage, with Lich Bane built, for *ALL* of your AP + your passive.

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I do my best to keep Mid as my domain.. Wards, while not listed in the buying list, are a very good investment, especially if they have a competent jungler. With wards dropped on each side of the river, very often you can push the mid tower *while being on high alert, and on guard for anything*. When you can do this well, you can survive the jungler trying to gank and get back to the tower. Until you can do it well? You will die horribly. Try only as you feel safe, or if not in ranked, whenever you please.

On Blue buff-
If your team has another AP, you can often pass blue off to them because of having Clarity. If there is not another AP? Get blue from your jungler and hold onto it like its made of gold. Midgame, the CDR is a nice touch and you will have the AP to actually be effective with it. But if its being offered and no one else needs? Take it and love it like its your only child.

This is my first guide Ive written for League, so any constructive feedback is welcome. Thanks for reading!

( Contact me in game too, id love to discuss any possible improvements. )

Title Explanation:
I will type "DERP CANNON!" in /all whenever I get a particularly trololol worthy kill. Sniping an enemy that would have likely escaped?
Picking off that enemy that is trying to 'b' under their tower?

Its my small amount of trolling I allow myself.