Pros

Extremely mobile
Pokes
Burst Damage

Cons

Slow wave clear
Can't poke through minions
Low sustainability

Ezreal is one of the most dynamic and versatile carry's in the game. No matter what build you use, he is able to poke from range, stay out of harms way with quick escapes, and burst people down with spells and auto attacks.

However, each one of the 3 builds has a unique purpose.

The Hyper-carry(Yellow) build is designed to give the player very high overall damage, with power house items such as Trinity Force and Infinity Edge the player will have the means to make short work of any target through a combination of burst damage and attack speed. This comes at a risk however, you will be building very expensive items so completing them can be difficult and consequently getting stuck in item "nowhere land" is possible if you fall behind.

The Utility(Blue) build is the more slow and steady alternative, sacrificing damage output in the early stages for more survivability and kiting potential. With this build you are deciding that it's not up to you to be the biggest damage dealer but rather a pest which people can't stop. The damage is fine, but it's rather low when compared to more strictly offense oriented ADC's.

Starting out with a Doran's Blade and life steal quints will solve the problem of sustaining for the rest of the game. This will especially pay off in the laning phase allowing Ez to trade throughout.

Yellow

Getting a Sheen early is normally the best choice instead of a BF sword because this will be built into a Trinity force as soon as possible.


Trinity Force is the most stat effecient item in the game, and it just so happens Ezreal uses all of the stats it gives. The attack dmg, attack speed, crit chance, and spellblade will make you an enormous damage threat. While, the ability power and slow chance are an added bonus. This item should be gotten first because of its all around strength.

Berserker's Greaves will give you attack speed for all around more damage and dynamism.

Next pick up an Infinity Edge and become a hyper carry. Triforce spellblade plus 250% crit damage from IE will leave opponents in ruins before they realize what hit them.

By this time the opponents may have built up some armor so pick up a Last Whisperer to shred that. Otherwise the armor will mitigate a large percentage of your damage.

Then top off your damage output with a Statikk Shiv giving you more crit chance to go with the EI bonus, attack speed to do more dps in fights, and a nice aoe magic damage proc which works off Mystic Shot.

As a final item I recommend Guardian Angel as a well rounded defensive item to make sure you can survive both poke damage and burst damage.

Blue

Getting a Sheen the first time you go back to base should be a general goal during the early game, with this item you are able to have much more power in lane than lets say with an early Tear of the Goddess.

Tear of the Goddess is an important early pick up after Sheen to allow frequent ability use and early stacking into Muramana.

Boots of Ionian Lucidity will give you CDR, allowing for even more frequency of AOE slowing spells.

The foundation of this build is in the Iceborn Guantlets, the early strength of Sheen combined with the ability to constantly slow targets is the purpose of the build. This will also give you a significant amount of armor, some cdr, and some AP as bonus stats.

Picking up a Manamune early is usually a good idea for some extra AD and getting a Muramana even sooner.

The next fundamental item to this build is the Muramana. With this item you will have the AD stack with Sheen and increase damage of basic attacks and Mystic Shot; and the ability to toggle it for the necessary burst damage to keep him a major damage dealer later into the game.

By the time you have completed IBG and Muramana the opposing team will have likely picked up armor items, making the Last Whisperer the best choice to instantly shred through it.

Blade of the Ruined King is then the natural next item, propelling the damage of this build to a new limit, allowing for an extra attack in between Mystic Shots. This also will give him life steal and true damage (based on health) as an extra bonus.

To finish off the build pick up a Maw of Malmortius to prevent magic damage (the last weakness of the build) and to continue increasing your own damage output.

Bottom Duo

During the early game Ezreal's ability to poke with Mystic Shot should allow him to annoy his counterparts while he slowly farms. By level 3 he has the potential to burst a champion that's been poked down prior, this is especially viable with a support who can initiate.

He may be pushed back to his tower if the opposing ADC is a pusher because Ez doesn't push back very fast. This can be bad because you can't control the lane but it also can be good because it sets up for a potential gank. When receiving a gank try to use arcane shift in a timely way to get a full burst on the target.

If you fall behind, just focus on farming and don't try to do to much because your damage output can be very low if you aren't caught up on items.

The strategy should be to gain early lane dominance to not fall behind on items, to avoid having an insignificant mid game.

Yellow build will allow you to become a massive dps threat immediately into mid game while Blue build will be useful for kiting but not for dps until later on.

Ezreal's versatility also allows him to be effective with most support champions.

As the game progresses into mid game it is important to keep Ezreal farming (like any ADC) which may not be an easy task because of his slow wave clear. Like always Ez is extremely difficult to pin down for a kill but you can be pushed out by harass dmg because you don't have much sustainability. What is key to remember in skirmishes is to poke form range until the moment there's an opportunity to go in and use his burst damage potential (this will be more potent with the yellow build). You must decide when to use your Arcane shift to go into a fight, and when to save it to get out. For maximum efficiency try to get your team the buff from using your Essence Flux on them (this will also proc spellblade). Don't be shy about using your ultimate, it's a fairly short cooldown and it is relatively strong for skirmishes early on an AD Ez (because it scales with AP), but can always be useful for clearing waves and finishing off targets later.

In full blown team fights it is very important to not get zoned out and only be able to poke which can be a natural tendency for Ez players, it is important to take chances to go after important targets and utilize his burst damage potential. This requires exact timing of Arcane Shift and proper maneuvering in the battle. It is difficult to go into detail because every team dynamic is different but a tip is to circumvent the front line if it is zoning you out.