User blog comment:YourPrivateNightmare/The mystery of Blue Ezreal/@comment-5514182-20130613000852

Blue ezreal is effective because all the items compliment eachother.

Spells gain additional damage from muramana, gauntlet, elder lizard, and BORK.

39% CDR allows you to spam spells. You can spam because of all the Mana and Mana Regen.

Last Whisper allows the on-hits to penetrate enemy defenses. Almost same AD as a normal build, and Ez gets attack speed from hitting spells, which he can spam.