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.
Corki is a very offensive character with good abilities to get away, gank, and control his lane. I'd suggest you take the +180 health gem, because he has good damage from start. Going Phage is good for hunting. The reason i dont go frozen at start, is the very high cost, and the fact it is not that much needed at start. I admit this is a copy of another build, but i have some changes to make for this build. For example some early life steal to keep him in game. Ignite is good to finish off his enemies, and ghost is a nice ability to hunt them with Phage. Going bot or top lane is a nice idea for survival, because he can function as a carrier. Read up on corki if you want this build to function, because he can be hard to play.
P.S. If you think there should be made any changes please comment and give us some advice.