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.
So most people would look at this and say "what? Not ad or ap ez? Forget it" however, I find this to be one of the most effective support and gank ezreal builds out there.
Regardless if you start mid or lane, Your tactics will be the same, DON'T CHASE! This is not a good early game build, however, they won't be able to chase you either. You probably won't have to tower hug at all, but if your with a tanky champ, you'll do fine.
This is where you'll start to really shine. By now you'll orobly have your boots and TF, working on your first phantom dancer. So you'll be doing around 100 Dmg per second, which is fairly good for right now. This is also where your going to want to do a little bit of farming to max out your gold intake to buy your goods nice and fast. Never be left alone with this build, you are very vulnerable and probably couldn't 1v1 anyone at this point. But if your with a tank, you could most likely push 3 enemy champs away if not kill them (USE ESSENCE FLUX!). Remember, this is mostly a support build.
By now you should have gotten a black cleaver and all that's left is to get you last phantom dancers. Again, never go anywhere alone, unless farming near your base or a little juggling. Remember to always save your ult until theres a really weak enemy thinking they narrowly escaped death with a sliver of health, until you wreck their world. Use your essence flux as much as possible to mainly help Allie but also slow your opponents attack speed.and when in the middle of a big team fight, spam your mystic shot to max out your passive for an extra 50% attack speed, then you'll have over 300% attack speed!