When I play Ezreal, I like to go Trinity Force, and then build him like a normal AD (IE, PD, etc).
Trinity force gives him so much power early on because his Q will applies on hit effects, so the enemy is perpetually slowed from the Phage, plus you have one of the most mobile AD carries just hammering away at you.
I feel like he's one of those AD carries that absolutely needs to win bottom lane or he'll get outcarried late game by a large margin - you need to win your lane early to get an advantage and carry that advantage the entire game, because you'll probably lose in a straight "carryfest" later on.
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