This Lux guide will not only keep your team alive, but also keep the other team dead. My teammates and I have found much joy in the contributions that Lux can provide a game. Anything from poking at the opponent to containing them in a team fight. As a support player you will get a lot of assists as Lux, however you will also get kills and you team will push ahead. This guide is to give you a place to start while using the champion Lux, enjoy!

The point of your masteries is to complimenet the the skills, runes and items that you have. Lux has a lot of ability power possibilities however if you want to keep your team alive then you must be able to control lanes, poke, and protect. Most of my mastery choices are defense because it helps strengthen Lux's weakness.
Defense Masteries:
Resistance (3) and Strength of Spirit (3)- help gain more health back as you accumulate more mana.
Hardiness (3) and Harden Skin (3)- Gives Lux some armor and allows less damage to be taken.
Defensive Mastery (2)- The main reason for getting this mastery is to allow other masteries lower on the chart to be upgraded, however less damage will be done by minions.
Veterans Scars (4)- This mastery is huge because it gives you more health and even though it is only 48, early in a game that is a lot.
Ardor (3)- This is upgraded for the ability power portion of it, but enjoy the attack speed too.
Tenacity (1)- As a weaker piece of your team this will take some of the damage if you are targeted (which you will be if the other team is smart).
Offense Masteries:
Cripple (1)- Gives your team a better chance at killing a targeted tank with more health.
Archmage's Savvy (3)- As Lux this is an obvious mastery since you will be AP (I hope).
Sorcery (3)- Allows you cooldown reduction which gives you more chances to poke and also control your lane.

Lux is given a set of skills that are great for keeping your team alive and the other team dead. First off I like to get Light Binding. In a 3v3 Light Binding will allow your team to quickly get two kills. Next Lucent Singularity will allow you to get into a fight, get away from a fight and most important control your lane. Prismatic Barrier will help keep teammates as well as your own health slightly higher. Finales Funkeln is your ultimate and it is huge. Now most people think pile on the ability power, that is useful but also get cooldown reduction so that you can constantly laser people!

The use of these Tier 3 runes can really help you. I dont like to just stack ability power since I have items that will do that during the game. I dont want to have to buy too much mana but I still want to be able to scam and poke whenever I can. The Greater Mark of Potency (9) is the ability power that I will gain from my runes. The Greater Seal of Intellect (3) is so that I will have more mana during early game without having to buy it, and the Greater Seal of Replenishment (6) will gain more mana back so I can continue to control my lane. The Greater Glyph of Intellect (4) is a huge boost to the stats for mana and the Greater Glyph of Insight (5) will give me some magic penetration to make me more affective. Finally, The Greater Quintessence of Intellect (3) gives me 112.5 mana which is a full ability early in the game.

The point of buying these set of items, as has been stated earlier is to not just get ability power, but also mana regen, ability power and most importantly cooldown reduction. Starting off you want to buy the Meki Pendant and a Health Potion, that way you can stay in your lane and keep using your abilities. Next build your Ionian Boots of Lucidity as fast as you can, they help reduce your cooldowns. Next build just Archangel's Staff. The next few items are mixed to build Rabadon's Deathcap and Nashor's Tooth. You aren't buying Nashor's Tooth for the attack speed but it is welcomed. Next Deathfire Grasp and wrap it up with the Void Staff.

Pros- Allows you to control your lane.
Can poke at enemies often.
Late game you can control some of the OP champions.

Cons- You will be targeted first.
Compared to others you may be slow.