This is a very fun way to play Ezreal, I only reccomend playing around with this in blind normals. I've been having very good success with this build, I may try it in ranked soon if my success continues.
Start boots+3. Max R>Q>E>W.
You will counter most top lanes heavily in early levels. Use your range to your advantage to deny them CS for as long as possible. Get E at level 2, it's a great escape/gap closer.
Masteries- 0/21/9 (take mp5 and mana from utility, and armor/mr/tenacity/hp from defensive.
Build order- boots+3, tear, sheen, catalyst, DEFENSIVE (either chain mail or negatron depending on matchup), finish first major defensive item (either glacial shroud or banshee's veil), upgrade boots (I like merc treads or Ionian), build Vamp Sceptre to be turned into bloodthirster late game, finish second defensive item (shroud or veil, whichever you didn't build first), Manamune, *Situational*
End game build 1- (2920 mana, 185 armor, 110 MR, 2165 HP, 262 AD)
Boots of choice, Muramana, Iceborn Gauntlet, Banshee's Veil, Bloodthirster, Guardian Angel
End game build 2- (3070 mana, 165 armor, 80 MR, 2415 HP, 292 AD)
Boots of choice, Muramana, Frozen Heart, Banshee's Veil, Trinity Force, Bloodthirster.
You wind up being super tanky with a great escape skill, global ult, sustain, and still able to deal huge damage with the muramana toggle.
Build 1 Q damage (full mana, toggle on) : 115+262+8+(175.2)+ = 686 dmg
Build 2 Q damage (full mana, toggle on) : 115+292+6+(184.2)+ = 748 dmg