Today we see many koreans using the Spirit of the Lizard Elder on Ezreal because it is so cheap. The advantage of Black Cleaver is: it gives 10 more AD, you trade the passives and the regen for flat and % Armor Pen. + Health and the Brutalizer will help you out early.

I still like the Bloodthirster more than the Spirit, the True Damage is just too low.

If you need an explanation for the Blue Build, check the forums, mostly it is huge damage because of the IG/Muramana synergy, an awesome 30% AoE slow to make you the most annoying Kiter ever, 39% CDR for your Q (also great with ult), and tons of poke on your Q

PROS:
- Super easy to play
- Kiting on the next level
- Laning will be easier than with the standard build
- Huge Armor Pen.
- You rarely get caught
- You rarely run out of Mana
- HUGE range with Q (1.1k)
- HUGE damage with Q (Muramana, IG, BOTRK, every 0.5 sec)

CONS:
- Not an ADC how you know them
- Very Skillshot dependent
- Small damage on Auto Attacks