Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
This build is good for Solo Mid and Laning. However, you'll benefit more if you get Mid. This build is designed to take advantage of Lux when she's the most dangerous, Early game, while shifting into a support role for late game. While Lux can have an amazing late game, I personally feel like you sacrifice too much survivability to maintain that Late game viability.
The description of this build will be extended at a later date when I have time to write one up in full.
In the mean time, enjoy. Rate and comment.