Important things to note about AD Ezreal.
1 - Ezreal lacks any kind of natural CC.
2 - Most of Ezreal's damage comes from his Mystic Shot spell, besides auto attacks.
3 - His damage output is reliant on the player's accuracy with Mystic Shot as well as having a clear path to the target. Which means his damage output can vary greatly depending on the situation, such as in messy team fights where he is unable to focus fire. However, given ideal circumstances, AD Ezreal has among the highest raw DPS output coupled with the ability to kite effectively.

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Standard Ranged carry spells. Get positioned. Chase. Gtfo.

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Works well as you have a free blink anyway.

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The new exaust Is very good as a dmg reducer against a 1v1 mid and rendering a target almost useless in a team fight, as you have no cc it's good as a slow to chase and a slow to escape. make sure you put a point in masteries if you plan to use it.

+Or

Will probably need to build this is you don't have the runes or you're team has 4 people more suited for mana buff. However, this hurts you're core item build.

Makes your Q hit 100% more.

Built from sheen, great all around item, speed, hp, mana, atk speed, slow, crit chance, and 150% bonus dmg proc on your Q.

Shreds armour, this build will do around 90 armour pen with the runes and this on 3 stacks, and tanks will feel it. another proc with Q.

Very viable item, sometimes rushed before a triforce for the armour pen and attackspeed burst.


Optional 6th item depending on situation:

Pros

Perfect Mid.
Spammable skills.
Great escape.
Usefull Ult.
Has alot of mana mid game so can spam spells
Best dance in the game.
Semi decent Armour / Magic resis / hp.


Cons

Squishy!
Vulnerable to CC.
Targeted first.
Some difiiculty to master.
Slight mana issues.


Play Style:
AP Ezreal is a great assassin. With Clairy he can have lots of map awareness and snipe people with ults or counter many junglers. E does lots of damage so always make sure when it hits the nearest target you hit the enemy champ. In team fights you wanna kinda just relax and use your ult when enemy team is in a bad position. Just sit back and Spam your abilities and don't auto attack unless you going in for the kill.

Early Game: Lvl's 1-5
Ok so you are either in mid or taking a 2v1 solo for your jungler. As AP Ezreal you always want a solo lane. Play very defensively only going in to last hit with auto attack or a well placed Q. If they try to zone you out of XP spam them in the face everytime they try. If you get zoned out of XP you will be in deep trouble. Harass little and go back to base as soon as you can afford Tear of the Goddess. (have your jungler cover the lane for a lil till you get back xD)

Mid Game: Lvl's 6-11
Ok now you have your ultimate and your ready to play aggresive. Ping for your jungler (or a team mate) to come and gank and make sure to focus the one player. Secondly make sure you land your skill shots. Anticipate where they are gonna be once your move reaches that point. Use your ultimate to either open up a team fight or to kill someone. Your going to want to gank alot or stay in lane going for clean up shots with your ult in other lanes (clary) so tell your lanes to tell you if someone is low hp and went back Clary ontop of tower usaully and ult. This method makes sure you get the kill and don't waste your ultimate.

Late Game: Lvl's 12-18
Ok this is where you shine!! Team fight time baby!! Ok so in team fights always try to hit the most enemies with your ultimate you usaully dont want to use it on one person unless its there carry. So after you use ult or if you havnt used it yet just sit back in the fight and dont get focused use your abilities and spam them alot!! Never push the turret by yourself (unless whole team is aced) because you are very weak at pushing them and will likely get little progges and ganked in the process.